I'm looking at soda blasting and doing a barrier coat after this season. From what I've read the barrier coat has to be done just right so it cross links the layers. I need to research this further, but I got that much from what I've read so far.
If you are going with the new barrier coat after the soda blast job, be sure to let the blaster folks know to take it all the way down to the gel coat. It is still a lot of hand and machine sanding after the soda blast.
I used the MAS epoxy materials, the slow stuff, and rolled it on with 1/4" foam rollers, it was easy to roll. The ratio is 2 to 1 resin to hardner for MAS so I mixed 24 ounces at a time, 16 ounces of resin and 8 of the catalyst. Stirring it with a paint stick worked Ok but if you have access to a drill and a paint stirring 'beater' it would probably be easier and more reliable.
The slow epoxy did not produce any amino flush, I rolled the coats succesively but had to stop after three coats for weather. Roughing up for the 4th coat was not easy but I had a contractor pack of sanding disks handy from the first part of the bottom prep.
Hope you folks are having some summer in Maryland, it has taken until August to see some semblance of summer in Massachusetts and even now it cools into the 50s at night--so much for localized global warming?