Your time is valuable, do not waste it on games you don't want to make! Speak up!
A little about myself, I am a pixel artist and I have been making games for 5 years.
A couple years ago I was looking for a proggrammer, After posting around for awhile I finally found one! After talking for a couple weeks, we became really great friends! I thought, for the most part, we had similar taste in games.
We made a couple game jam games and we really meshed well together! Both of us were highly self-motivated and we pumped a few games out onto Newgrounds in the coming weeks.
So after deciding, we worked well together we wanted to tackle a bigger project! After a lot of arguing on what genre of game we should make we ended up landing on Perillux. A futuristic cyber action beat-em-up! This wasn't a theme I was very happy about. But I was too shy to speak about my true feelings, I didn't want to upset my new friend. Perillux took a year to finish. And I didn't put my full effort into it because it was not a game that I wanted to make. But after 3-4 months into the project, I felt like the door was shut, We couldn't just stop making the game, We already invested too much time!
So what we ended up with was a half-baked really bad game! It was just a huge project that at the end both of us hated! By some miracle, it made it through the steam greenlight process. However, we never released it.
At the core level, I have so many problems with this game. Yet, I did not say a single thing. It was a really tough lesson to learn when I saw the result was this monstrosity of a game (If you could call it that).
I could go on and on about how I was too much of a chicken to say anything or to confront my friend about how many things were wrong with this game. I just don't want you to make the same novice mistake I made. Don't make something your not passionate about and if you are... change it, fight it, or it'll come out terrible(at least in my experience).
(Not trying to drive traffic to Solarbyte, I am no longer with them. Just for those who are curious about what the game looked like.)
The greenlight page: