if they are unreachable how did the archers get there...
They're unreachable for cavalry, can't just give archers 100% immunity to one class while still being able to efficiently damage them, it's fucking retarded, and, getting up on those ruins is impossible unless the my old friendchers up there are outnumbered 5:1 or shit like that, and even then they can easily exit the ruin and kite over to some other ruin 'cuss there are like 50 of them in every fucking map.
For an archer to work effectivly he needs to be able to focus on pewpewing, and not constantly be on guard for backstabbing melee and outoftheblue cav.Let the other ranged and shielder deal with ranged nests.
Ok, and for a 2h hero to be able to work effectivly he needs to be able to focus on fighting, and not constantly dodge arrows and be on guard for backstabbing melee and outoftheblue cav.
And for a cav to be able to work effectivly he needs to be able to focus on backstabbing not dodging arrows.
You can watch out for cav while you're reloading your bow, aim once you're done, then shoot, then watch out, then shoot.
As a horse thrower I think your best utility is as a cav hunter, particularly HA's. With the speed bonus change that devs have said is already in the works the class itself will probably become a lot deadlier.
The reason I enjoy being a horse thrower is that there ain't nothing I can't fight, except for retards with great cover on unreachable ruins which are fucking retarded.