I'm doing that exact thing. Visually, pulls look too heavy on the uppers to me, so we opted for knobs there only.

Yes, I did that as well; pulls on lowers and knobs on uppers.

That's pretty standard...

We don't like knobs.

We bought only 4" and 8" pulls for our full kitchen. All the cabinet doors with side hinges got 4" pulls oriented vertically, all the drawers and pull-outs got pulls mounted horizontally, generally 8" pulls (narrow drawer and narrow "tall things storage" pull-out got 4" horiz pull). Here's a few example views from our "knobless" kitchen (kitchen in as-lived in state, not cleaned up for photo... sorry):

I guess I didn't explain myself well enough...sorry. I know many people put pulls on lower drawers and knobs on upper cabinets. I'm wanting to put pulls on all the lowers INCLUDING some lower DOORS. So, the bottom doors would have pulls and the top doors would have knobs.

It will look fine. I've seen it every which way, and it's all good. To me, placement on the door is more important to get right, than being in error of mixing knob and pulls.

We did just what you're thinking out doing. Everything below the counters has a pull. Some are mounted horizontally (drawers), some vertically (doors). Everything above the counters has a knob. I worried that it would look a little haphazard and so purposely picked hardware that would sort of fade away (ie brushed nickel on white cabinets, versus black on white cabinets which would really stand out). I'm happy with how it turned out!

ETA: I do suggest drawing it out. We printed out our plans without any handles at all. Then I drew in different options. You could also wait until the cabinets are all in, then use painters tape to mark out options as well.

Pulls vs. knobs:

You can also use knobs on lowers. Again, opinion.

Of course you can go with pulls-down /knobs-up ... it's quite common:

As for knobs "catching" your clothes and pockets, you can avoid this easily enough. It's a matter of choosing the right style. Look at the pulls in the two pictures above; they will never catch your clothes because they have no "poke outs" to catch. In contrast, look at this style -- they'll "catch" because they're straight /have "poke outs" on the ends.

One particular problem to consider with knobs: They may spin. I have birdcage knobs in my kitchen -- something similar to the picture below -- and although I like the look, I hate the function. Some of them "spin" when touched, and they end up sideways, which annoys me to no end.

I wish I'd gone with a similar look that was more firmly attached:

Final thought: In my new kitchen I intend to use all pulls. Why? Because I'm planning for aging in place, and pulls are easier to use than knobs. I actually went to Lowes and opened doors pretending that my hands didn't work as well as they do now.

I did not misunderstand my answer remains the same.

bemocked...what did you use for your back splash choices? Both are very unique...at least to me! (I know this thread is a year old but am hoping you may see this question anyhow.)