A camber kit would help the problem, but a good alignment tech would be even more valuable. You should probably stay away from the dealer for this, as those folks will tend to fall back on Honda’s specs - which are obviously faulty.
No, it will not void your warranty - at least not in the sense you mean it.
Longer lasting tires? - Well, pretty much any tire is going to last longer the OE tires. Those tires were designed to roll easy and give good fuel economy, and Honda got that by specifying low rolling resistance - and that means sacrificing wear. If you want better wear, look for high UTQG treadwear numbers. Just be aware that you’ll be sacrificng fuel economy.
Oh, and ride quality has nothing to do with tire wear.