Don't take this the wrong way...but to me it seems like you are not commited to any of these tricks. You mention on all three that you don't have the handle. If you want to land a trick you have to have the handle. No trust me on this, I know that these tricks can be scary. I would do the same thing on backroll attempts, letting go of the handle and essentially stopping my rotation and landing on my head. The best thing you can do is hold on. It took me a long time to realize this, but it does hurt less. Same w/ the tantrum, I would let go of the handle and under rotate it.
I think that once you committ 100% to one of em' you will land it quicker than you think. I would go for the ole' backroll. Just hold that handle in and don't let go until you hit the water, and I bet you will land one in less than 25 attempts.