I have been on T for 23 days and I have doubled in size (its still not that big yet though)
Trans guys usually range from 1 inch to 3 inches, the 3 inches are really lucky.
it just looks like a small penis with a foreskin.
I guess it depends on the STP, some STP's may not work if you have had too much growth.
Bottom surgery is your decision, some guys may feel comfortable enough with the growth they have had.
I dont wear a packer, I have one for special occasions, but nah I find them uncomfortable, and I dont feel the need to wear one.