New and updated for the javascript version!
First of all: the interface. Oh boy.
The UX is (still) not great and in many ways is a downgrade from the flash version. You can't see all your stats at once (I'm looking at you, Libido) or how they change when you use a transformative. I still fuck up the "which key/button embiggens the map and not the avatar". There is way, way too much stuff hidden behind the... Codex? V key? Companion Cube? button (no tooltip, so can't tell!).
Worse, there's massive inconsistency: in the codex page, buttons appear and disappear and move around and don't keep the same key shortcuts so you have to remember every single damn layout and note what buttons have appeared or disappeared since the last time you used them. Some places you just move out of. Some places you have to hit "leave" - and is that G or space or have a key equiv at all? All of those! Will there be an "Up" button for stairs? The Q one will always light up, but in the main area sometimes there'll be one, sometimes there won't. Same thing for sleep, except the "can I sleep or not" thing is hidden in the X menu. Are there further submenus? There's no indication one way or the other: Codex -> Appearance has no indication that you''ll get manipulable suboptions in there (with submenus inside of that)! And then some menus just randomly break (eg try and equip a new piercing in 0.9.19). Some of the map icons are still inconsistent (people in their apartments or not at Tarkus, stairs going up or down or both).
Secondly: all the old broken stuff from the flash version just got forklifted in and is still broken. The mimbranes? Still full of bizarre things (like, you must have toes in order for them to hook on to your feet, and you must have your feet infested before your face). The race calculation menu still shows everything as being out of 16. Mhen'Ga still has woefully incomplete content (venus pitchers, anyone? everything associated with vanae, including the stuff that was mostly coded before people left) and inconsistent mechanics, etc), Tarkus still has bizarre side effects with some of the sexbots and/or hand so's quest, some of the waifus' interactions are still broken, etc. Some things got worse, but few of the extant bugs got fixed.
Thirdly: it's been almost nine years since waifuquest got started; the first git commit was 31 oct 2013. And speaking of:
Fourth: please refer to the "source code access" thread; while the javascript version is easier to directly inspect in the browser, having an actually nicely formatted set of code rather than a minified comma-laden monstrosity still is not nice. It was nice having the webpack-derived source-maps for a few glorious days, but those disappeared pretty quickly. The tone of discussion in that thread from staff has not been, shall we say, non-combative.
I don't mean to say that everything is terrible and awful but there are some really glaring faults, especially around the UI and interaction; if the earlier stuff could be remade/remastered along the lines of FIRST-14 that would help - but there's too much stuff in the interface that's hard to find, hard to see, and hard to use.