Good advice here about re-coating and car topping. Your Sea Bee should be fine for the conditions you will encounter, too, but - of course - the most important factor is you. Develop a "bomber combat roll," and you'll be much more likely to both enjoy yourself and be successful in heavier conditions.
Lots of practice is the key to developing that roll . . . .

As for car topping on your Subaru, one of which I have and have cartopped skin boats something like 10,000+ miles on, attach at least part or some of your straps to the fore and aft portion of the rack, rather than solely to the athwartships cross bars. The cross bars can come loose, and/or break (unlikely, but one of mine did). I have replaced mine with carpet covered 2x4s, though that is a bit of overkill.

Have fun!