I hope expanding outside the home game is ok with this topic. The best long-term game I ever played was probably way back in the mid 2000's when we could still play on Party Poker here in the States. The fixed-limit Omaha hi/lo cash games were a frigging gold mine, and I supplemented my income and eventually quit my job for a few years just playing online.
My single best cash game experience ever was in 2007, my first trip to Vegas. My wife and I had partied at the Bluff Magazine WSOP party and then headed back to our hotel room. After 2 hours of sleep I woke up with the urge to play some poker, and took a cab over to Bellagio.
I bought in for $2,500 into a 40/80 mixed game. It was Omaha hi/lo, Stud hi/lo, 2-7 Triple Draw Lowball and Badugi. I had never played Badugi before, but it was similar enough to the other games that I picked it up quickly. I consider all of those my best games, but it didn't hurt that I also ran like a frigging god that morning.
I would hit Aces full and the nut low and get three people calling me to the river, it was a beautiful thing. In the span of 2 hours of playing I racked up a profit of $2,700. So I cashed out for $5,200 (in yellow $10 chips!)