This is a tricky one (aero bars). I switched from a road bike to a TT bike recently for many reasons. One of them is that when you look at the angle of a road bike, especially where the sear post is, and compare it to a TT seat post, you can see that the road bike saddle sits further behind or far back from the handle bar than TT bikes.
This makes it hard to add aero bars to a road bike as you might compromise your form. However, my issue was also that I am short (5’7), my bike was a medium, and I just had issues reaching the aero bars. To avoid compromising your form, I recommend to either read a lot about them online or go to one of the bike shops coach AJ mentioned during the kickoff meeting (or in the follow up note to my kickoff meeting follow up post on here) and ask them to fit you and help with you with measurements.
Re. Trainers: it depends on how dedicated you’ll be and how much you’ll use them. I got a basic cycle ops (magnetic) and now I regret it. I was also looking at cheaper versions and didn’t get a smart or fluid trainer instead. However, the one I have does the job and I am somewhat happy with it.
The main issue is that it’s a bit loud when you have to go fast, and that you can’t really adjust it (if it is too tight or loose) unless you dismount your bike and pause your workout. I’ve heard and read great reviews about cycle ops and I got mine off amazon since it was cheaper on there (about $130) last year.
Hope me that helps