Maybe I'm in the minority but I don't mind the combat at all and I would personally find it a bit sad if it went away. For many, combat is an unnecessary roadblock but I think some combat sprinkled in in the right amounts adds to the anticipation for what is to come next. It should serve as a minor roadblock, preventing you from running from scene to scene. And with the capturing mechanic it's even better since there's consequences if you are not quick enough to save Sana (or if you just happen to accidentally target the wrong enemy
). I would bet that those scenes are more more effective due to being tied in with combat and the gameplay, but I suppose its probably possible to get that feeling from another mechanic rather than rpgm combat and there might be other ways to "set up roadblocks" rather than combat too.
So I'd put my vote on keeping combat for the next game, but as I said I'm probably in the minority on that one and I would be curious to see what alternative you would be able to mastermind up.
I feel the same way you do. I enjoy having the combat and dungeon sections. At least for me, it feels like it helps with immersion and/or engagement? It's hard for me to explain, but I like the game having combat elements so that I have to actually make choices and do things rather than just rush ahead to the next scene. Plus, combat introduces additional NTR opportunities. There's the mid-combat capture scenes, as you've pointed out, and I feel like the stuff that results from loses in combat against the bosses wouldn't be as meaningful without having actually lost in combat.
And besides that, there's little gameplay bits in combat that can add up to enhance the NTR experience. Having to choose between Anon and the other party member for who Sana should heal if they're both low, getting to directly see just how much less damage Anon deals and why having a third member is necessary, and reorganizing Sana's equipment are all things that are due to the game having a combat system. (To expand on that last part, iirc Sana starts with a ring equipped that she had gotten from Anon, except, well, a ring that you can buy from the store gives better stats. Sorry Anon, but numbers need to go up~)
And I feel like the game implements the combat relatively well. It's not so easy that you can just braindead mash your way through, but it's not so difficult you're ever really stuck anywhere. A nice challenge without getting obnoxiously hard. I suppose locking levels to story advancement helps with setting up the difficulty curve, because it's done well. And the lewdness is enough to spice up the combat so that it doesn't feel like a chore without taking over combat encounters wholesale.
In fact, one thing I was kind of hoping for would be the bosses capturing Sana mid-battle as well. It'd match the pattern of 'center/important monster can lewd Sana' and, well, why should their minions get all the fun?
I dunno, that's just my thoughts on it.