Hayo! Breakin' it down:
1. Yep; this was a time-saving measure because of the ridiculously short development cycle. Right now they're baked in together, but that's because we haven't really built out any of the UI framework yet. Sprites, background, and the UI will all be drawn separately.
2. Double-yep. As well as animation for the enemies idling, attacking, and possibly during battle sex, although that might be limited to certain special enemies. And, of course, any extra-battle sex (either an encounter that goes south or goes exactly as planned) will also have accompanying art - as well as some generic animations for certain activities, including game over splashes and generic animations.
3. Absolutely. There's a ton of stuff that isn't yet implemented - all in total, there are 3 basic combat stances, 6 advances stances, 5 "positional" stances, and a number of sex stances and other special stances, all of which will have a lot more options in terms of skills than they do now - so the number of skills will likely hit low- triple digits. The combat system as it is now is purely proof-of-concept - none of the enemy stats or skills are finalized (enemy health is only as low as it is to make it easy to 'skip' combat), and while I have done an initial first pass of what classes will have what base stats (and there will be some tweaking for character customization), most of those stats are currently not used, whereas all of them will have uses both in combat and out - that's designed, just not implemented. Battle sex will be a tactical element to tire out (stamina system - only partially implemented, being fatigued will lower attributes), distract, or satiate your enemies, with the (design) intention that willingly and strategically using sex in battle will make battles overall easier, while making it more and more likely that your character will abandon and/or be forced to abandon their quest as they progress if they're constantly doing it, either because they pick the wrong partner or are too enticed by an offer of... companionship.
And though you didn't ask specifically about it - world map traversal, generation, towns, resource management and equipment will all be implemented and expanded upon.
4. Definitely don't have a release date in mind yet - there's still a ton of work to be done. This is just an initial build out of the core gameplay loop and some iterative design. Only reason we've even set this up on itch at this stage is to participate in the lewd game jam because it seemed like fun and gave us a nice deadline to hit. We've got a long backlog that will only get longer as we dive into each system, and we're a team of two. So far we've made pretty steady progress, but the final game is far in the horizon, so any release date would be a guess.
Thanks for the questions - if you've got any more, please, feel free, and suggestions are also welcome. We'll probably post up on here with a list of planned gameplay and UI systems so that it's more obvious what's in the wings definitely and what's still up in the air.