You could weld copper pipe together
If you really want to get OCD--then just wrap two chunks of 10AWG cable together and solder it to the amplifier terminals. The other end can be soldered directly to the crossover board.
However, then you'll notice how thin the capacitor and inductor leads are so time to upgrade those.
The funny part about all this is why? If it don't matter, then go after things that do matter to get actual improvement. Nothing wrong with overkill, I do it myself. I purchased a 100 foot spool of 12 AWG copper cable, mainly because I can use it for 30 foot runs for surrounds, I can wire up subwoofers to handle 4 ohms at over 1KW at a distance of 25 feet if I like. It is crazy to wire 10 foot runs of the stuff for my mains--but it does not hurt anything and no matter what crazy project I'm working on, it will work.
I view speaker wire and cables like I view downforce wings on cars--they can help until they don't. If I was running a 20 KW Powersoft amp with 4 ohm subs 50 feet away, I'd be worried about it. Since I don't and never will, there is no reason to go nuts on "future proofing" my cables.
If you really want to worry about the last 0.001% of resistance in your cables--directly solder them to the crossover boards and the outputs on the amps. Get rid of that nasty electrical resistance of the connections. While you are at it, check to see if the crossover wiring uses crimp terminals or is soldered directly from the board to the drivers. THAT makes much more sense than increasing the size of the cables past 12 or 14 AWG in traditional homes.
When I built my vertical line arrays a few years back, I directly soldered all 81 speaker drivers from their terminals to the crossover board. A friend asked if it was for audio reasons, my reply was "No, it is done for reliability reasons in that having 162 speaker connections done with crimp connectors would be a disaster if one slipped off. Consider that is 162 connections for each speaker not counting the series/parallel connections to get to the crossover board so figure around 400 solder connections for the pair. I solder to keep my sanity"
So relax, a lot of the "improvements" in audio are done for many reasons besides sound quality. If you feel the need to improve something, try XLR balanced connectors, room treatments, PEQ or room calibration. If you want massive speaker wire for overkill's sake, do that AFTER you get everything else done first.