Elbows overlapping your knees is pretty common when in a tuck on the drops.

Now, if you like your position climbing, that suggests you like where your hips and shoulders are. There is something you can play with that will make the feel descending quite different but will not appreciably change your comfort climbing (or yhour aerodynamics going fast). You can rotate your handlebar location up and forward about and arc centered at your shoulder ball. Don't rotate the handlebars; you seem to have them set up nicely. Instead, think about your position as a viewer would see it from the side. Your arms are basically sticks you can bend at the elbows and that you can swing about the balls of your shoulders. As you swing them forward, your hands come up, in a near flat arc over a say 6" distance. Now to simplify things, you can replace that arc with a slanted straight line. For me, that straight line would have a slope of roughly two cms forward over 1 cm up. In fact, quite conveniently, it is closer to 2 cm forward and one cm up and back along the line of the headtube, steerer and stem.

This means I can set up a bike with say a 11 cm stem slammed or raise it 1 cm and go to a 13 or raise it 2 cm and go to a 15. They all work. And guess what? As you do this with your bars, your elbows are doing the same thing to a lesser degree and pulling away from your knees.

This "Rule of thumb" is only dead simple with traditional horizontal stems. But it works regardless. If you have a threadless setup, sketch out what you have with a ruler and protractor, then place a mark one cm up and back from your current handlebar tops along a line parallel to your headtube and 2 cms forward horizontally. Draw a line between your current handlebar position and your new mark and beyond. Figure out what stem and spacers you need to put your handlebars at a new location on that line and try it.

I have several bikes set up with the handlebars in very different places along that line. The bikes are quite different and fell quite different but all climb like customs (fitwise - several are not light at all workhorses!). And all feel right from the start, even if my last ride was on another bike. (I do have to think about where my bars are the first time I ride no-handed. I have forgotten and missed!

Document what you've got before you change anything. any setup that climbs effortlessly is a keeper. Best dimensions are vertically and horizontally from the bottom bracket to the tops of your handlebars and from the BB to either the nose or a place you can find again for your seat. (I like to put a piece of tape halfway between the nose and back. Easy to find again, little affected by changes of tilt and pretty close to my sitbones, the point that matters. I have even made permanent marks there on my seats.)

Ben