If your going to carry all the time, weight will be one of your biggest factors in the comfort department.
The lightest double stack 9's are Glock and Walther P99.
This needs to be weighed against the benefit the xD has, as it is some operation/trigger to what you have now.
Then again for CC understand all these, even in their compact/subcompact models are very bulky and difficult to CC all the time, in all weather. It can be done, just not comfortably or well.
Possibly you should consider a single stack 9 if constant CC is required. Kahr P9, Kel-tec PF9, Walther PPS are all good choices.
PS- I recently made the switch due to ammo cost and weight. Went from all steel 1911 to the Glock 19. I love it, am very happy so far, however the difference in triggers is going to take a lot of getting used to. If you go doublestack, the XD9compact might win out over its lighter competitors for the same trigger advantage.