I'd be in favor of it. I mean I'd pay about $10-$15 easy and highly likely subscribe provided I enjoyed reading it.
As for content what was said above really, tips, reviews, post-game bits, hell even a write in section for airsofters to write in tips of their own or ask questions. Maybe even a feature on how to build a good kit on a budget.
I'd happily provide pictures I take and such if permited