The whole keeping track of who's there "helping out" and taking notice only means that someone hasta show up, go afk a bit, put someone on follow, and warp out a little early without being noticed and they get just as much stuff as Captain Endgame and his All Star team of campers.
Honestly, if you want your shell to work, point systems are the best way to go. Also, this idea to cross over into HNMs from SKY/SEA is one of the worst ideas I've ever heard from any shell, not just yours. Every shell and their brother attempt to do this. "ZOMG let's get finished with sky soon so we can do HNM" never works because you get 2/3 of your shell burned out in sky from the grinding out gods, and the other third bails after their done with their sky gear to join an established HNM shell that actually knows what they're doing in land HNMs.
Good luck with your shell, and I hope you succeed at breaking this trend. I'm just pessimistic about it. I've seen soo many shells like yours break in the first few months because you simply cannot get enough people.
Advice: Stop making new shells and join ones that are successful already. Reasoning: Established shells have experienced players, working strategies, most people have a half or more of the stuff they need, and lastly when you join an established shell it gets bigger and thus moving it toward the roster needed to take down HNM.
/endrant.