I went through this dilemma. My cabinetmaker told me that shaker 5-piece drawer fronts are made two ways: most commonly, the center panel is a thin piece of wood, sometimes just 1/4" thick and flat on both sides. In the other option, the center panel is actually a reversed raised-panel, with the flat side "out" and the raised side "in". In that case, it's a full 3/4"+ thick. She advised that it's better to have the pulls in thick material (especially for big heavy drawers) so in the first case they should go in the frame. We have the reverse-raised-panel type, so ours are in the centers.

We also are going for a contemporary look with our shaker style cabinets. I think a few things affect whether shaker looks traditional/craftsman-ish or contemporary: 1. I think generally slab drawers look more contemporary. Having said that, we went with shaker fronts for the large drawers and slabs for the small drawer bases, to provide balance in our particular plan (we have a lot of large drawers). 2. The size offset/depth of the panel. I don't see people discussing this very much when they describe their cabinets. We will have a 1/8 inch offset as opposed to the more typical and more traditional 1/4 inch offset. I think the more shallow panel looks more contemporary as it approximates a slab look more (but still keeps the panel interest). 3. Color of stain. To me, a dark stained wood (expresso, cordovan) in a shaker style looks more contemporary than the natural wood/natural stain look. (I think this could be just me, though) ;-) 4. And of course, the hardware you choose, as well as countertops, backsplash, etc., makes all the difference in the overall look!

I have much the same.... a combination of shaker and flat, although my kitchen is all white. I did pulls on everything and love the look. All of my pulls are horizontal as in the picture you posted, and my tall cabinets (fridge /freezer/ pantry) have 12" vertical pulls. As your picture shows, my pulls are not huge. In fact, I think some of mine are smaller than the ones shown (although I love the look you show as well!)

I wouldn't worry about it for drawer fronts. If you were putting a knob in the middle of a 2ft square door and had the drawer loaded with cast iron pans, over time you might see a warp in the MDF. If you worried about the knob pulling out for some reason, just use a washer along with the screw on the inside of the drawer to distribute those forces more.