I'd never do a 150m dive ... too much deco and bailout required is ridiculous. Your views will differ...
However, we can agree nobody needs a 150m reel for their SMB. For line laying a simpler (less snaggy) reel is needed so the 150' ratchet is an odd idea.
Whilst you are spool fan, I hate spools and will use ratchet reel with my SMB. I find a reel to be forgiving; if I let go is stays put, I can hang bags off it and still us it, and, if I feel lazy, I have a winch
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Custom Divers 70m ratchet reel with bungee to keep the crack-bottle SMB attached seems about right.
If the skipper says SMB from the seabed then that is what I do. Why play smart arse with the guy who is about to rescue you?
When I send the bag from the seabed I also start my ascent, and use the reel to keep myself moving ('Mary Poppins ascent'). It's a lot of fun, and takes a bit of practice, but avoids a lot of winding and deco. For 60m dive I find the SMB reaches the surface about the time I get to 35m, so by time I've stabilised the CCR I'll be at the first stop.
Back to the OP, a reel that is adequate for the dives you do is all you need.