50 is not a time that solo becomes tough. Though the horde equivallent to the quest that opens the cauldron quests in WPL would be a pain to solo. The ali only has to kill 10 skelatal flayers, and 10 of the other mobs in the cemetary near Chillwind point.
When I saw the horde equivallent concerning poping the tent and what not with the scarlet crusade, I nearly fell outa my chair. I did solo it on my now lvl 70 orc hunter; but all I can say is not the next time. I'll get a group, in comparison to the alliance equivallent, that was just rediculous. Hmm, if one wanted to be a synic, they could almost ask if the ali getting easier quests is why they don't perform as well in BGs
End game, one would be hard pressed to explain that way though, as ali side there do at times seem to be more guildes in the higher lvl instances. On the other hand, PuGs for 5 mans ali side can also be painful.
Winterspring opens up soon. Only problem is if you want to solo play, latter on grinding, repping, making money, etc becomes the only viable activities. With my hunter having exalted with the Wintersaber trainers (no not this last patch, but last May), Scryers, Kurenai, and almost exalted with the Timbermaw (also done mostly before 2.2), Consortium, and Revered Argent Dawn; it does grow old. I can rep yes, but by now I also grow tired of it faster then before and have to take breaks.
There are dailies for Ogri'la rep, many of which can be soloed (though watch for those who try to steal one's rays, play with the lights on that simmon game at another "console" or what not. Heck, I had some horde land where I was getting ready to laso an aethar ray, to then kite it back. As he coudln't laso, he killed the thing on me before the laso animation finished. After harassing me for awhile, I finally agroed several boars, walked them over to him, and feigned death on his arse. He got the point and stopped killing my rays as I went to laso them.
Only problem with Ogri'la dailies for you, is the chain to open them involves several group quests killing the various Sons of Gruul. You'll have to group to open those up.
Don't rule raides or what not totally out though, even if you have to be explicit on what times you can/can't play and find a guild that won't try to make you play more. Grinding isn't exactly what I'd term fun, but to each their own.