Re: low pressure only in the kitchen
My guess is that there is debris blocking the line at the anglestop or where the kitchen lines "T" off the main lines. Try removing the aerator from the faucet spout and then closing the anglestop (not tight, just a few turns ) a time or two while running the water. While the aerator is off, disassemble it and clean out any debris that may be lodged in it.
I've heard of "backflushing" the plumbing, but have no idea how that is done or what it entails.
I suffer from CDO ... Its like OCD, but in alphabetical order, LIKE IT SHOULD BE!!!