Help! My system is very bright it hurts my ear

I don't see how the Aragon could be causing a brightness problem when it is playing on the woofer. Try using just one amp at a time, either one, with the high and low frequency terminals jumpered. If the amps are not matched to each other, that could lead to a tonal imbalance. Bi-amping is not as easy as just using two amps on a speaker, unless the amps are identical or you use something like a dual amp balancer. Don't spend any money on this until you have tried only one of the amps.

$200 spent on room treatment will make a much larger difference than $100,000 in cables. Treat your room.

Put panels at first reflection points, add a rug for the floor reflection points. Put some absorbing stuff on the wall in front of you or behind you to kill slap echo. You won't even recognize your system after doing this.

You're wasting your time pursuing anything else.

Get some good Cardas Copper cable Gold reference its older stuff but it will warm your system.  The tubes are good but can be different not 'better' different.  Try to get some Mullard E88CC the oldest versions you can get.  DO NOT get CV2493 I love them but they are sparklers.  Get rid of the Aragon, yes I know it's only on the bass or woofers but its dangerous to have around.  I would suggest getting Quad amps tube amps of course or Leak amps.  Finally get rid of the little Quads and trade up tp the big electrostats what number 898 or something like that.  Also try vinyl.   Best of Luck