Start small then, just 10, minutes or even 5. Anything is infinitely better than nothing.

I knock out 30 minute sittings daily. I wish I a) had that kind of time to devote and b) had the wherewithal to regularly sit that much. All-day sesshin is a killer for me after about two sittings.

What is this anxiety? Does it come from the fear of non-existence? I will be dead some day, and I surely don't want to spend my limited existence staring into the void. Gotta keep moving!

On the right time scales, is there even any difference between "staring into the void" or "moving"?

What difference will it make anyways after you're dead?

I do 4 minutes a day and find it good. 2 minutes just trying to blank my mind and 2 visualising nice stuff.

The point is to keep your mind focused on one still thought. Letting your mind wander around won't do much. Complexity of the thought should match your ability. Lam-rim says that more short meditations is better than one long meditation. Ideally, one would meditate 16 times a day. And again, the whole point is to stay focused on one thought.