@Damsel-kun Can do, I love sharing series I enjoy. Went through my completed and reading lists looking for Isekais that I would personally call better than this. Tried to separate personal taste from the equation as best I could, but probably didn't succeed, and regardless in the end what you enjoy always comes down to personal taste. Still, all of these are series I would at the very least be willing to defend my position on to some degree. Also restricted it to only series with the isekai tag, skipping series that aren't technically isekais even if they have a similar vibe, as well as series that currently don't have enough content to judge even if they are promising, and series that got axed even if the stuff up to that point was good (with one exception). Also just gonna clarify that when I say "this series" I'm referring to Savior's Book Cafe (realized as i was writing that might be confusing). Anyways....
*Tensei Shitara Slime Datta Ken - As much as I eventually grew to low key hate slime tensei for betraying my expectations (reading the WN at least) the manga is at the current high point of the series, which I like enough to give it the rec.
* Kumo Desu ga, Nani ka? - My personal favorite isekai once it reaches the turning point 200 chapters into the WN. The manga is not there yet, probably won't be for a while, but even before that it's still pretty good.
* Kimi wa Shinenai Hai Kaburi no Majo - Still in its infancy but has enough content to judge off of I would argue (though of course a series can always go downhill without warning). Radically different tone than this series though lol
* Isekai Meikyuu de Harem wo - I'm serious. If you can get past the fact it's smutty harem wish-fulfillment (nothing inherently wrong with that either, I mean hell this is pretty blatant wish-fulfillment too) then it's actually pretty well done. Even if don't care for the smut, the bandit hideout infiltration chapter alone I think makes it worth a look.
*Mushoku Tensei ~Isekai Ittara Honki Dasu~ - It's overrated and I can't stand the main character and haven't picked it up in 3 years. Still would admit it has its moments of brilliance though.
*The Villainess Will Crush Her Destruction End Through Modern Firepower - The art is what makes it IMO, and that's largely personal taste. Rest isn't bad though. Still arguably the weakest entry on this list atm.
*Isekai Maou to Shoukan Shoujo no Dorei Majutsu - It's unrepentantly trashy but honestly that's part of its charm and if you give it a chance it winds up having a lot going for it. Genuine tension, stakes, solid characters that actually get some development, interesting and well realized world, and maybe one of the top 5 isekai plot lines i've found. At the very least top 10.
*The Dungeon Master - I forgot this existed until a new chapter came out 9 days ago, that's how long it had been since it got updated. Good series, but chapters 2-50 are on not on mangadex.
*Isekai Ojisan - A satirical series that is somehow funny as hell while still doing a better job at just being a good story than the stuff its satirizing.
*Kenja no Deshi wo Nanoru Kenja - Not too much to say about this one, solid worldbuilding, nice bit of intrigue, characters can be a bit flat, but all around pretty good.
*The Wrong Way to Use Healing Magic - Interesting premise, good characters, some subtle intrigue, and tone strikes a good balance of comedic and serious. It does a lot of things right and not a lot wrong.
*Saikyou Juzoku Tensei: Cheat Majutsushi no Slow Life - Probably one of the weaker entries here, but I like it and think it does a good job giving a laid back vibe while still having stuff happen and providing just enough tension to keep things interesting.
*What Do I Do?! I Have Transmigrated Into the Weakest Little Monster - A chinese series, which all but guarantees it's going to be a at least a bit odd, but honestly once you get into it it's pretty good.
*A Simple Task of Providing Support from the Shadows to Defeat the Demon Lord - Way too low rated. Unique premise, interesting and well crafted world, smartly written, strong characters, great plot. Yes the hero is annoying, but that is the point, it's a characteristic being utilized by the plot, and will almost certainly be addressed with gradual character development.
*Tensei Shitara Dragon no Tamago Datta - Ibara no Dragon Road - One of my favorite isekai. I love the tone, the pacing, the world, the characters, everything. I just wish the pace of new chapters coming out wasn't so fucking glacial.
*Isekai Tensei Soudouki - I hesitated on putting this one in the list. The premise is fairly unique, the plot is interesting, and the tone is pretty well done. It definitely has its moments. Characters are pretty hit or miss though and it feels a bit too much like any other generic isekai sometimes. Really comes down to if its strengths overcome its weakness for you.
*Jui-san no Oshigoto in Isekai - Unique premise, interesting world, strong plot, decent characters. Not great, but I still think it better done than this series.
*I Want to Become the Hero's Bride ( ̄∇ ̄)ゞ - The one exception to no axed series simply because it's one of rather few shoujo isekais I actually like. A (mostly) nice mix of light wacky comedic antics from the MC contrasted against the seriousness of the rest of the cast and the situations. It is almost solely carried by that, but the characters are fairly well done too.
*Risou no Himo Seikatsu - A fairly unique take on isekai that derives its strength almost solely from the strength of its premise (though the rest isn't bad). Still, forcing a basic bitch everyman type protagonist to navigate court politics and diplomacy in a world he doesn't understand is inherently interesting. Still probably one of the weaker entries on this list, if you ask me.
*Saihate no Paladin - My second favorite isekai, it's just really well done with very few weak moments. An easy 9 right now and honestly has only been getting better.
*Tensei Shitara Ken Deshita - The best iteration of a standard isekai you are likely to find. Still dumb with plenty of familiar tropes, but manages to do everything well enough to still be a good series. If you are just totally done with dumb tropey isekai though this is probably one to give a miss.
*Jishou Akuyaku Reijou na Konyakusha no Kansatsu Kiroku - My favorite shoujo isekai, even with how weak I think the middle section is(at least the middle going off the current chapter count). Manages to find a good mix of comedic and serious that I am particularly fond of. Plot and characters are fairly strong too.
*Yasei no Last Boss ga Arawareta! - I'd put this at about the level of Kenja no Deshi wo Nanoru Kenja.
*Honzuki no Gekokujou ~Shisho ni Naru Tame ni wa Shudan wo Erandeiraremasen~ Dai 1-bu - If this had the shoujo tag I feel like it kind of deserves it would be my favorite shoujo isekai. All around strong series with little to complain about.
*Wanwan Monogatari ~Kanemochi no Inu n shite to wa Itta ga, Fenrir ni shiro to wa Itte nee!~ - I don't know if this deserves to be on this list, I just think it's cute and and funny.
*Isekai Omotenashi Gohan - The better version of this series if you ask me. Isekai shoujo slow life romance featuring an adult woman and some background plot, but with stronger characters and world building. The manga ended long before the LN though, I believe, so it's a bit incomplete.