Oh sweet. An isekai argument. I'd actually argue that you can count on *two* hands isekais that are decent (what's this? Someone who has an inkling of faith in this block standard genre?). If you want to find isekais that were actually written decently, I'd look into the first isekais to come up with a new trend. What we're seeing 90% of the time are bland rip-offs of isekais that have already been written. To give a few examples of these:
1. Block Standard adventurer isekai: Musokou Tensei was the first. You can give it shit, but most things were given some thought before being executed.
2. Revenge Boner Isekai:
Shield Hero and Aferita are examples. Not a fan of this genre ngl. Evil for revenge's sake isn't my cup of tea. Common trope here.
3. Reincarnated Monster:
Slime Tensei, Kumo Desu, and Re: Monster are the earliest big examples. Not a fan of the last one, but I can't deny that the author was decent despite my cripes about the "plot". Slime Tensei had an excellent start but got overly-complex. Kumo arguably had the same problem. Biggest flaw is escalation.
4. Isekai Otome game:
Bakarina and Duke's Daughter are the earliest big names I can think of. This one is my favorite since the character focus forces authors to have some kind of depth to their characters. Authors get a lot of freedom if they have their characters break away from the main plot line too.
Overall: the grand majority of Isekai is shit because they copy what works. The first ones to work are generally what you should look for if you're looking for decent writing. There are some that don't follow this trend of course, but they're rare. Isekai Paladin, and Grimgar are examples off the top of my head. Others I havent mentioned but would suggest are Evil God Average and Bathroom Goddess. Both of these loosely fall under Isekai Slice of life