Sounds like you only tow 3500 today with 6100 lbs of capacity.
7600 is 1500 lbs more capacity than you have today.
7600 is more than double what you need today. I'd say that plenty of headroom for your next camper.
You could easily tow something loaded to 5500-6000, depending on your family size and the terrain.
Our 7000 lbs rating tows our 5200 lbs loaded camper just fine.
Go for it.
thebrakeman ('70), DW ('71), DD ('99), DD ('01), DD ('05)
2004 Surveyor SV261T (UltraLite Bunkhouse Hybrid)
2006 Mercury Mountaineer V8 AWD Premier
Equal-i-zer WDH (10k), Prodigy Brake Controller