Starting TVHM: I recommend either a Harmony build with a Com that buffs Lifetap, or a Cataclysm build with a Binder COM (buffing Reaper). You want the capstone skill in either case for slagging, which is vital for Maya in UVHM and still really helpful in TVHM.
As you run through TVHM there are a lot of reasonable paths to follow. I like grabbing Suspension and Converge from the Motion tree (possible to get a capstone + Converge at L42), which synergize well with either of the build strategies I mentioned.
[Aside: If you’re leaning towards an eventual Thoughtlock build, my own feeling is that TL works much better with Cataclysm (Ruin re-procs whenever Sub-Sequence procs!) than Harmony].
If no TL, after you get Converge, I’d say switch toward investing in whichever tree you haven’t built in yet (If you built Cataclysm, start Harmony towards Wreck and Elated. If you built Harmony initially, start Cataclysm toward Chain Reaction and Reaper.
Starting UVHM: One thing you can build toward in UVHM is a Blurred Trickster build. IMO this build does NOT require top-tier endgame-type gear to be workable and its emphasis on Lifetap and CR - excellent mobbing skills - makes it great for a playthrough. My suggested framework for a Trickster build is Ruin, 1 point in Lifetap (for the COM buff) and Converge as well as the skills necessary to get that far (CR, Reaper, Wreck, Suspension, etc). This requires you to be level 63, which means the full Blurred Trickster experience isn’t available until later in UVHM, but can be run for a good long stretch of leveling between 63 and 72.
You can get a semblance of it earlier if you are willing to sacrifice some DPS. Go only as far as 5/5 CR in Cataclysm, and add another few points to Harmony to take Scorn (for slagging) and you can get there at 57.
It’s always the low - mid 50s that are the struggle. In that range Ruin + Converge, building towards Wreck and Elated as you go, is one way. You’ll start UVHM with good DPS but relatively little healing (Sweet Release might be necessary at the start). An alternative with more healing but less DPS is Scorn (with Lifetap, of course) + Converge, building down Catclysm toward CR.