From the standpoint of any kind of paying user - I think allowing the "Night Time" dark interface theme is quite important.
If you look at the way Unity has restricted a Dark Theme to Pro users - and the resulting uproar among users - it may save you from this kind of flack if you give people a break, now. For many it is a health issue, not a luxury feature or an advanced feature.
I think the tier price points are really reasonable - for nearly every conceivable user - so no change is needed there.
But, the name "Indie" for every platform I can think of implies "making games for money". Perhaps you could consider naming the $4.99 tier to "Enthusiast". I would avoid the name "Hobbyist" like the plague - or even "Amateur". Nobody likes a label that puts them in an inferior category.
This is why, in serious forum circles, the term "Newbie" should be utterly abandoned.
Greg Smith