My brother and I are working on a game together and we can't stop arguing over one thing: Is it bad to add things to the game purely for the sake of fun? "Fluff" I guess you'd call it.
For example, our player is able to use a whip. Well, I thought it would be cool if he could use the whip to swing from pegs attached to the ceiling. Does it serve much of a purpose? No, not really, but it's fun and can be challenging if I make it that way. His argument is instead of swinging from the pegs, we could just add some small platforms that are difficult to cross. Boooooring. More walking and jumping..just what we need

Also, bombs are one of his secondary weapons. We added them because they're ranged and have good AOE. Well that's cool, but why have bombs if you can't blow shit up? I suggested we add some destructible blocks that block paths and stuff. Just for the hell of it. Blowing up stuff is fun, and if anything can change how a section of a level might work. He wants no destructible blocks whatsoever.
One thing that's often brought up is simple, temporary upgrades. I suggest multiple small upgrades like one that sets enemies on fire when you attack them, which deals 1 dmg per 50 milliseconds. It is kind of pointless since you can just hit the enemy one or two more times and kill it just as quickly, but come on, who doesn't like to set things on fire? Enemies flash red and emit flame particles. It's fun. Some enemies might even go berserk and run wildly back and forth. He, on the other hand, wants a
single temp. upgrade which increases your attack damage and range. That's it.
I guess it comes down to
A) Have a lot of neat little things that are fun but don't really add much to the gameplay.
B) Keep it clean and simple and focus on the core gameplay. No fluff or "distractions."
In the end, I'm programming it, so I can add these things if I want..but every time I'm about to I ask myself if it's really worth it. Will the player actually enjoy and appreciate these little things or is it just extra crap to fool them in to thinking there's more than there really is?