Lyft is a decent chance of a tip (I get one at least every 3rd ride), and I believe it has in general slightly better pax.
Lyft is much slower, but I make a little more per ride. I very rarely get a Lyft-Line, but too often get Uber Pool (pings are maybe 40/60 Pool/X).
Unless going after incentives, I keep both apps open - especially in the suburbs - but only do the Uber app when in the city in the weekend night hotspots and it's really hopping. Then for a few hours, Uber keeps me going full boogie. Otherwise, I'm usually both apps going. My night's proceeds usually run around 3:1 or 4:1 Uber over Lyft, but I sometimes neglect Lyft a bit.
Lyft pax rate me better: I'm high 4.9x on Lyft, but only mid 4.8x on Uber. I suspect my Uber rating might be lower because I occasionally take pools when chasing incentive. I believe Pool is too often a rating killer.