First off, it doesn't look like the Casino Gaming and Gambling is going to be passed, it only has 8 followers and the person that proposed it has said he thinks there isn't much interest in a SE about gambling in general. As for you proposals:
I'm not opposed to merging Poker into here, but they are so until they change their mind it is a rather moot point.
I think this is a bad idea. For one in addition to not wanting to be combined with us Poker doesn't want to be combined with Gambling or Casino Games either, since while their game does regularly take place in a casino it involves more skill than luck and you aren't playing against the house. Also while Poker and some other card games like Blackjack make some sense being combined with Casino Games and Gambling there are plenty other like Dominion and other deck building games, and Magic and other TCG/CCG games that are harder to justify combining.
Here we have a clearly definied scope for our questions:
- Be playable on or around a table
- Have objective rules of play and win
- Offer dynamic challenges, either through other players,
randomization, or both
- Be playable by hand, by human players
implementing all of the rules
Poker clearly falls into all of those categories, which is why I'm not opposed to them merging into here, however not all casino games fall under that criteria, and gambling is not on topic here.
As Rainbolt says it seems like you are trying to avoid overlap, and I think having some overlap isn't a bad thing. Poker questions can still be asked here, and they generally get answered (the only on that hasn't was more about probability that poker anyway), if someone comes here with a poker question that is off topic we can always migrate the question to the Poker SE.
Gambling however is a completely separate topic from what we cover here, as such I do not support merging that proposal with us or expanding our scope to include it. If it can get enough support it can exist on its own, but not here.