3.5 or 5e for a group of new players?

[Kelb_Panthera]

It's not complex, making an "optimal" fighter in 3.5 is straight up impossible. Adequate is doable. And I think you are underestimating 2d8HP's aversion to complex class features like rage.

There's always an optimal solution. You've misunderstood the term if you think otherwise.

The 3.5 fighter can be made into a -huge- number of fighting-man archetypes. That some are more niche than others doesn't make them badwrongfun^tm. Unlike a barbarian, where you pick 7 feats over 20 levels, a fighter must select 18 feats before epic. Making the most out of that for your chosen archetype requires planning ahead and selecting suitable gear. It's just -not- as simple as it often gets down-played as being because "lol, fiterz suck. Play <insert basically any class but monk here> instead."

You want simple and straight-foward beatstick, you want barbarian. Rage is definitely a nice boost but you can get by without using it. You won't be the face-smasher supreme but, if you're going single-class to 20, that probably wasn't at the top of your priorities list anyway.