No problems with steel, or aluminum, or carbon...

Or titanium, or bamboo, or...

What are you really looking to do with the bike? 80% sure it's steel, yet you'd include a 29-er or hybrid on your list? Sounds like aluminum is a more likely choice for you, because then you'll have all three types of bikes still in the running.

Are you riding off-road, and will this include single-track? Go with the 29-er. Mostly roads? Go with the hybrid or cyclocross. Aggressive riding, with little off-road? Go with the cyclocross...

Your issue is not frame material, it's style of bike. The rest will take care of itself...