Trying to improve my catch

Today I went for a paddle where I was trying to figure out how to improve my catch. It’s been pointed out to me a few times that I don’t get my paddle blade fully “buried” in the water by the time I start pulling, which means I’m not getting full advantage of the most powerful part of the stroke. In part, that’s because I chose a very long paddle blade in order to make the catch a bit more gentle on my elbows, so I’m not sure I want to fix this entirely. But that said, if I want to get faster, I’m going to have to put more power down.

[youtube poxEhBJcEO4]

Here’s some stills from that video. I’ve tried to catch each one just as some whirlpools show up around the blade, indicating that power is being applied to the paddle.
My normal paddling position

With the shaft extended about 1cm.

With the shaft extended and my hands brought in 1cm.

I have to say, looking at the stills, I’m not sure that there is any advantage to extending the shaft. I think maybe I need to try extending it further.