I agree with the OP. That much gap in chainring size is a PITA to shift even when the setup is optimized. There is simply too much lag time moving the chain to the big ring.

I'm guessing you have compact cranks (110) so finding a 46-36 setup is easy. Go for the cross rings from SRAM, Shimano or FSA. Set them up as a matched pair and line up the timing marks. Compared to 52-36, or even 50-34, the shift is fast and smooth.

If you have a clamp on hanger it's easy to lower. If not a little file work in the slot should get you there.

Loss of top end? Doubtful. At 90rpm you're pushing 30mph, and most of us can't fight the wind resistance at that speed for very long. Another big benefit of the 46 tooth outer ring, IMO, is that you can run around town easily in the big ring and somewhere around the middle of the cassette, so it just plays nicer with parts.

Personally I wouldn't have it any other way, nor would any of the others who I've converted over.