You do mean a self-inflating DSMB, either CO2 cartridges or a ‘crack’ bottle.
No, I still use the traditional DSMB where you inflate it yourself at the bottom and send it up. I really like the idea of the crack bottle DSMBs, but I couldn't get over the issue of the water entering the bottle at the surface and slowly destroying the bottle.
I agree with you on the ratchet reel. It is such a benefit to be able to let it go and watch it hang in front of you without having to mess with a double ender every time. For deco stops, gas switches etc I think this is a big plus.
For the OPs original question, I still keep my reel and DSMB separate and attach them underwater. I would love to have them pre-rigged but the one disadvantage to a reel is the size and I am yet to decide on a good way to store them both together without them dangling in the way. Even with a smaller ratchet reel I struggle to fit them in a pocket. I totally agree though that it would be nice to not have this additional task loading at depth. I will keep experimenting!