v-brakes and cantis are both cantis, but it's easier than saying 'side pull canti' and 'centre pull canti', so I'll use the common terms.
so... a v-brake may be too much stopping power for your 700c wheels. It'll likely be more power than you need. A canti has much better modulation, unless you're buying really expensive v-brakes (I can hear your wife now). The other nice thing about cantis is that you can find used ones for free. Just ask around among riding friends. Someone will have an old part of mtb cantis collecting dust. Trade them some bike bit you don't need anymore. I'd never want to run a v-brake on my road bike, unless I was hauling weight. V-brakes are easier to setup and tune, but they tend to be on/off, which is something you don't want/need on a road bike. No finesse! I use some mid 80s dia-compe side pull calipers (road brakes!) with those wonderful koolstop salmon pads, and they stop very very well. I'm not familiar with dia-compe 986's, do they use brake bosses? Does your fork have brake bosses? If not, you're looking at a new fork too. Have you considered dual pivot brakes? Again, can be had for free.
best of luck in all your stopping pursuits!