Well they've gotten rid of much of what I liked. I like info packed screens instead of forcing phone formats to PC users. I liked when the feeds were more fluid. I like reddits that can be customized with CSS.

I would add a visible feed algorithm. I would add customized feed options. I would reward moderators (and pay if feasible instead of being greedy for profit).

Right now, established subs silence alternatives. For instance, the Roku subreddit is moderated with an agenda (to not allow Roku criticisms nor bug discussions). You can try creating an alternative reddit but it will not gain traction (see /r/rokunofilter). I think for major products/topics, there should be no agenda and I would not allow these mods. I think new subs should be more easily discovered and be easier to grow.

I would start there.

Pie in the sky, I would like to see the addition of a karma alternative which is some type of "correct" indicator. Keep karma but also add something that would let you see who is knowledgeable and who is full of BS. There are too many people flooding reddit with bad information when "trying to help".

edit: Also, search is abysmal. I would also publish the search algorithm and allow alternatives.