I do play online casino games occasionally, but poker is still my main thing. I like the idea of tracking both poker and casino results together. Setting a firm session limit is definitely important.
Mixing poker and online roulette is a quick way to rip through a bankroll. You can study poker odds, but roulette is just a mathematical drain over time rewards points aren't worth the negative EV. Strict limits definitely help, but end of the day the house always wins on table games.
I've played them and don't recommend them. I totally disagree with your point of view; poker and roulette are not comparable: the only variable in roulette is luck, and nothing else.