Small boats like an 18' can be OK on the lake but not on every day. Like others have said the broads are always changing and it can be quickly. I did do the broads in extremely rough weather 4 years ago in a 14' Starcraft closed bow (a very bad choice) and I know of another who did it
regularly in the 60's in a wood flat bottom 12' home made boat "Puddy Tat" Today I would suggest a 19' - 21' as the minimum size for occasional cruising on the lake. Also go for the widest hull width as that will help with stability in rough water too.
