You're pretty close, but I would describe it this way:
The betting round is over when:
A. There is only one player with a live hand.
-- OR --
1. Every player has acted at least once,
-- AND --
2. Every player with a live hand has either matched the maximum bet or gone all in.
The game you describe is common and can be found both online and live play. These are called the “wanna see a flop” games and can be quite profitable because these are easy games.
Basically your opponents need 5 cards - not 2 - to decide if they want to play or not. So they will call most PF raises. So I’m ok with your 8x and feel free to go higher than that,...
You are right. Hold em poker hands have 5 cards only (including any combination of a players hole cards and the cards on the board), there is no 3-pair and no extra kickers for hands like straights and 2 pairs.