Given the circumstances(the manga got axed, author had to finish in 2 chapters), the author managed to put out a fairly decent ending.
Sure, there are plot lines that weren't tied up, there was a 2 year timeleap and the unconditional happy ending has a bit different tone then the rest of the manga, but it's still much better than some other endings and certainly could have been much worse.
Pretty good read overall, sad that it got axed. Hopefully the next work of the author will get a better reception amongst Japanese readers.