I think everyone is giving great advice here accept one. The handlebars. If this is your first time off road, gravel or not, I'd recommend either a flat bar or riser with bar ends. More stable and can handle a heavier load. I kinda think you will have enough thrown at you that you will want something more familiar but that's just me.

Not saying that drops aren't a better choice long term but to see if you like it I'd be more conservative the first time.