You can do some really nice riding on V-brakes too. The best attribute of disc brake IMO is the smooth power modulation, and I am not sure that entry level disc brakes are noticeably better than v-brakes in that regard. If I had the choice of getting better forks/shifters instead of getting entry level disc brakes, I'd pick the former every time.
If the wheel is 'disc ready', it's not hard to install the brakes yourself (I installed hydraulic disc brakes on my bike when I was complete novice going through a phase of upgradeitis).
Does your LBS carry Giant bikes. Usually Giant gives you pretty good value for your money. You should be able to get a Ravel 1 if you stretch your budget just slightly.
Lastly, the difference between these bikes in the same price range are almost negligible. So stick with one that feel the best, and if they all feel 'good', just pick the one with your favorite paint scheme (I am completely serious).
It's more important to get a bike that makes you go 'DAMN that's a sweet looking bike' everyday than to get three extra gears that you most likely will not miss.