What is your event? Vert can make sense if it has a lot of elevation change. Distance for an ultra, hours maybe if you are mixing hiking & running or on a lot of hills. This is just from my experience of training for one year too, hopefully someone else will chime in.
I switched to planning in vert this summer after I signed up for a race with a lot of vertical (~9k of vert in 25 miles.) It seems the hours & distance sorted themselves out as well along the way. I also trained in hours earlier this year for a 15 mile race and that worked well. I haven’t trained in distance much myself but I do a lot of hiking that is on steep terrain so distance isn’t as useful I find.
Earlier this year I tried to use the ATP with a TSS basis and fairly quickly had to give up on that. Also the guys here have mentioned not using the ATP — I agree with that. I built my plan using their books and just enter it in a few weeks at a time. I also drew a picture like the sample training plans they have in their book which I found helpful.
I also picked up on the technique of using a stub workout on Mondays where I label the type of week (recovery, build etc) with the goal vert for the week for easy reference.