On the Mat Day 409: How to Complete the Triangle versus Large Strong Opponents

Things are picking up lately at the club. There are more people attending class than ever. This may be due to the end of summer and the dojo feeling less like a sauna. I've been working on two things recently.
1) My double leg takedown.
I used to be really good when I did Pancrase way back in my 20s but that version was with no knees touching the ground. I now use the BJJ style of tackle with the knee touching the ground and the leg slipping around then using the head to fold the opponent and spiral him to the ground. I use the big punch bag at the gym which goes all the way to the floor for kicking to practice my double leg. Each repetition I try to make sure my body is parallel with the bag. That is, my entire chest and stomach touches the surface of the bag as I come up after dropping my level. This stops the opponent from easily stuffing the takedown by dropping his weight on you because there is less of my back showing for him to crush downwards. I was successful at one attempt versus a big strong guy who has previously stuffed my previous double legs.

2) My triangle finish versus bigger opponents.
This has been a pet peeve for me lately. I work my arse off to get to the triangle position only to have a bigger stronger opponent stack me and pass my guard. Huge effort from me to get there, little effort from him to pass. I've discovered a couple of things by researching and through asking K-sensei.
a. If you feel the guy is thick and can't get your legs around him transfer to omoplata where you can sweep, submit or even move back to a better triangle position.
b. Grab your ankle with one hand, and push on the knee with the other hand so that your leg is perpendicular across his shoulders and back shoulder shrimp backwards to break his posture and then re-triangle the legs. This is demonstrated very well by Renzo Gracie.
c. To stop the stack. Use your hands under your knees to create a frame with your elbows sticking into the floor. Alternatively, pull on his shoulder and collar of the side opposite the one he wants to pass around to. This will anchor him in place while you can re-triangle your legs the opposite way then pull on the head to finish.

I will be trying these methods as much as possible because there are so many wasted opportunities for triangle that I am losing out on.