I started wtih a TA05 two years ago and slowly added all the R parts including the lightweight suspension. Obviously, I spent a lot more doing it that way and it worked out for me. As I got faster, I made the car better.
I actually prefer the regular TA05 oversized suspension arms and hubs and bearings over the lightweight versions that come with the TA05R for performance and reliability.
I ran the dog bones for a while, but noticed a big difference once I added CVDs front AND rear. I think they are the only thing you must upgrade out of the box. Unfortunately, that will cost you roughly $40-50 + cost of the kit $160 and you are over $200.
So for $200+, you might as well go for the TA05R version. The TRF shocks, CVDs, aluminum turnbucks and aluminium spension blocks are worth every extra dollar the TA05R costs and then some.