Power meters are really useful for a few things: #1 - adding a level of precision to training that heart rate cannot give you. Especially for short intervals, HR responds too slowly. #2 - benchmarking

If you stay with it, a TRX is a nice addition to the home equipment if you have space to hang one (watch out for counterfeit TRXs on Amazon/ebay). Lots of options for body-weight exercise + flexibility