Mark and others here are the true experts, but I see some very solid and consistent recommendations and advice that often appear on these forums. I'll try to best summarize my version of all this information:
1. Most cooks can do 95% of any standard kitchen tasks with 3 to 5 knives.
2. Trying to purchase a set of matching knives is very limiting vs. selecting the best model of each type according to your particular needs and budget.
3. The #1 most used knife for most people is an 8" Chefs/210mm Gyuto or a 10" Chefs/240mm Gyuto, and this is the best candidate for spending a bit more of your budget percentage on a really nice model.
4. Other very useful knives for most people include: a paring knife, a good bread knife, and a smaller 4-5" utility knife/petty.
For me personally, a good 210 Gyuto is a revelation of great cutting performance vs. Henkels/Wustof. I prefer the 210mm size. This knife is not the kind of thing to use hacking through frozen foods or banging through tough butternut squash, etc. It's awesome when used as intended and a stunning performer.
I use this inexpensive but very solid performing 10" Chef's knife for tougher jobs or bigger stuff like watermelon. http://www.chefknivestogo.com/fofi10chkn.html
Great bread knives that are commonly recommended here are:
Victorinox 10" http://www.chefknivestogo.com/fowabrkn10.html
(I have this one and it works very well)
Tojiro DP (Out of stock right now)
Richmond Artifex 270mm Bread knife http://www.chefknivestogo.com/riarbrkn27.html
. (I bet this would be a great performer)
You'll find lots of options for petty/utility knives. Common lengths are 120mm and 150mm. Frequently recommended models with a western handle are these:
Fujiwara 120mm stainless: http://www.chefknivestogo.com/fufkmpe12.html
Fujiwara 150mm stainless: http://www.chefknivestogo.com/fufkmpe15.html
Others here with much more experience can give you Gyuto and paring knife recommendations.
Enjoy the diversity of having so many great brands at your disposal and take advantage of that luxury to assemble an awesome performing collection for the wedding present that might just be the most used and appreciated that they receive.
Don't forget to make sure they have a good, safe knife storage solution as well to keep the knifes in top shape.
I hope this helps and congrats on the upcoming nuptials.