Almost. The role of dilithium crystals has changed somewhat. As of TNG their purpose is "merely" to be a conduit for antimatter and matter streams to merge and form they patented "trek plasma" which powers their warp coils (and also flows all over the ship so that the panels can explode dramatically during fights).
I won't disagree too much about the subspace field part, although I must point out that the shaping of the field does matter to warp efficiency.
Moreover, are you familiar with the reason for the Trek logo? If you are then you should realize a minor flaw in your explanation of warp.
And when the bubble does collapse, it drops the craft wherever it was when it entered subspace. That's why the Warp10 shuttle didn't end up billions of lightyears away; It was only any distance away because of the Warp9.X speeds it was travelling at before it hit Warp 10.
Now if that were true, wouldn't it be completely useless to even think about achieving Warp 10?
Additionally, if Warp 10 is the theoretical "infinite speed" and they have to "accelerate" to Warp 10, then it's a complete fallacy.
Voyager should have said it was a way to boost Warp efficieny ten-fold or a hundred-fold. But to claim the Warp 10 business is again ridiculous ><
Can't say much about transwarp. After all, it originally was conceived to be a next generation warp drive and is now something different.
[edit] I realize the problem now. I'm not being too clear on my position.
All I'm really trying to say is that the Trek producers have a habit of messing things up to the point where it can't make sense.
That doesn't really stop me from watching Trek anyways.
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