I'm doing the same thing this winter
I'm gonna run an ice boat this winter. Easier to create awareness and at a lower cost being the first (I.e. no competition). And with the ice flow last winter they will all leave their ATV's and snowmobiles behind if its affordable? I'm thinking $30 a head, but that's on the ice and I think I can run 30-40 people a day. Shanties are extra, heat is really extra extra! LOL! I think your onto something. Charters are confining to specific groups of folks and head boats are lets say are awkward. Be the leader and cut your own path.
Buy an ad in the B.G., Defiance, Napoleon, Tiffin, etc markets. They have bass boats and run abouts but we know they are smart enough not to take them on Lake Erie but they still want the eyes. Just a 3"X4" in the weekend sporting section. Keep your costs and their travel to a minimum. Word of mouth and referrals after that.
Tonight I eat Porterhouse and Morrells? Tomarrow eyes, Saturday eyes, Sunday eyes. All with big (JUMBO) Yellows! Yummy!
Good Luck and Good Fishing