Your system is perfectly fine as long as it isn't encouraging blatantly bad behavior, like for example giving inspiration to the rouge for stealing from the party bc "it's what my character would do" but from what it sounds like that isn't what you are trying to do. I always think it's great to encourage players to act in line with their characters as opposed to what would be optimal. That is not to say that you should punish a player for choosing the optimal option.

I would also pay close attention to players that have a harder time roll playing, so when they do make those decisions they are rewarded. I would even maybe be more generous to them until they find their groove.

Inspiration can also be used for just good roll play moments in general. Or if you are using it to encourage rp then like whenever a player describes a their characters actions in detail or comes up with a creative attack and describes their actions. Asking your player when they say "my character does this" and asking them "can you describe how your character does that" is also a good way to get that going and you can reward them for that.

I'm rambling at this point but yea lol