You do know a system very close to this actually already exists in Mordor, right? People are gladly carrying you for a small sum of gillies. They can even carry you through more complex fights like Titan.

What you seem to ask for is eighter a P2W system or a way for you to never having to play with another player.

In case 1, go and play GW2 or other F2P/P2W MMORPGs. In case 2, go and play single player FF games.

Also, DF is not nearly as bad as it's reputution, most people complaining about it are in dire need of carrying. Only instant in DF I can think of that I think MAYBE you want a premade for is Titan HM.