I'd be inclined to go with a Tubus Tara and leave it at that. It's light, solid, secure and puts front panniers in the best possible position. If at some point you want to reduce your load to one set of front panniers and top of rear rack load it'll be there.

If you're considering a front rack for muliple load configurations this type can work well but it helps to move the panniers back so they overlap the brakes an inch or so so that handling doesn't get weird. The linear pull brakes makes that easy whereas cantilevers will wear a spot in the back of the panniers. I have one of these on my CrossCheck with Ortlieb Classic front rollers providing enough adjustability to fit on the short rack but it takes a few wraps of Gorilla Tape to reduce rattling on the skinny rack. Not all panniers can fit on this kind of rack. I didn't bother to use the under fork crown mount but used rubber covered p clamps off the cantilever bosses. I wanted every millimeter of room for the front fender and this allowed me to get the rack as far back to the head tube as practical. With the cantilever bosses providing side to side support the fork crown tang can be cutoff. Another configuration for this rack if you're down to one set of panniers and going for lighter weight is to move front panniers to the back, get two 13liter dry bags and clip them together then drape over the rack and along the supports. It'll take some figuring out so the bags are absolutely secure with zero chance of dislodging into the front wheel.

VO Constructeur Front Rack - Racks & Decaleurs - Accessories

for a 15lb load it doesn't seem worth getting one of those big multi level combo front racks