I don't know if they do it anymore, but Romines High Pockets near me in Milwaukee but they had poker tourneys in the pit and that seemed popular.
Cue Club in Waukesha does casual poker tourneys.
In my experience, I don't see any crossover between the players in pool and poker, but if something draws a crowd, hell why not.
If anything, I always thought a casino / pool hall would rake in the big bucks for obvious reasons. If anything, I see a lot of the pool players near me hitting the slots machines and video poker machines scattered around the bar areas. Imagine if you had some real card tables, dice tables, real slot machines.... Gamble on pool, get pissed, go lose more at craps, get drunk, go play more pool. Why would anyone ever leave until they're broke?
Fortunately my state is extremely strict with casinos and who gets to own em. So unless some of the Tribes around me start getting into Billiards, I think it's never gonna happen beyond some VLT slot machines at the bar.
Otherwise, I think one of the better avenues is just having a general fun / family atmosphere during the day, that switches to the bar / real pool player crowd at night. I imagine a place that has a nice bar, decent food, 10-12 tables, games the kids can enjoy like foosball, darts, shuffleboard, video games (arcade area from this decade) and the biggest thing - having decent facilities. I avoid places like the plague if they have dirty / bad bathrooms. Poor drinking water / expensive drinks. Poor HVAC is a killer around for some places in the summer and winter. I've got places I don't go to in the summer because their AC is broken or underpowered and it gets to 80* and humid inside. Then there's other places where I refuse to patronize in the winter because their heaters are so bad it's like 60* inside and drafty. Hard to get comfortable shooting wearing a winter jacket to stay warm enough to shoot loose.