Being out-shined by another player *sucks*. They literally take the situations you anticipated being a part of away from you and leave you just sitting there.
I really don't understand why two PCs can't both contribute similar skill sets. Happens in my games all
the time. Two is better than one, not worse, for the party. Two Rogues halves the chance of failing to pick the lock. Two barbarians beats the enemy down twice as good. Two assassins assassinates twice as much.
You must have extremely low threat games if risk of party failure isn't a factor, if the PCs are just
there to show up. But then there's no need to worry about lacking a tank or other role.