Almost any class can do well now w/o a bot, but if you're talking solo you have to realize that a strong solo class generally has to have one or more of the following:
1) Stealth - Hands down this is the best defense in the game, as you'll avoid countless zerg deaths from visible FGs, small-mans, etc. It provides that ability to select targets to attack, and also often becomes a means of escape from adding visible classes.
2) Speed6 - Again, a great form of defense by avoiding conflict with superior numbers. All speed is good, but naturally having Speed5 + perma sprint (aka. Speed6) is the only one that will allow you to often outrun FGs...they usually give up quickly if they realize you're a speed6 class and have a head start. (Only Minstrels, Bards, and Skalds have Speed5. As stated above, Bards are largely a grouping utility class, Minstrels can generally only do well solo with a pet, and Skalds are hands down the best choice for you as far as music classes go, because they're both wanted in groups and extremely competent solo and don't need a bot to be strong.)
3) Charge - In combat speed3 and CC immunity. This great ability is useful both offensively and defensively. When fighting near friendly safe places, you can often manage to escape FGs and other teams when you don't feel like fighting. One of the best parts of Charge is it's low RuT, so it's usually always available at least once per fight. It's also a great ability offensively to avoid being CCed while you charge into combat. (Vamps, Mercs, Savages, Valks, Zerkers, and BMs have Charge. Yes, Midgard has 3 Charge classes. /cry)
4) Crowd Control (CC) - Especially the AoE kind is highly preferable for any solo class, and ranges CC can even buy you escape from enemy FGs sometimes.
5) Another escape tool: SoS (speed5 classes only), Phase Shift (Sojourner ML ability), Vanish (Assassins only), Archer RR5s all have a speed3 component that can't be broken by CC or damage
Of course you also want to be able to do solid damage to kill your opponents as quickly as possible, because the longer it takes the higher the chance of other people adding in on your fights.
As you can see Friars don't fit in real well there. They are a good solo class as far as damage and abilities go, but they have no CC, are highly susceptible to CC themselves, and have no escape tools. (Their RR5 might work, but that's about it.) So I personally wouldn't recommend a Friar for solo, but they are a solid grouping class if specced for it. (Which naturally then excludes soloing. /cry)
Heretics and especially Reavers are also strong solo classes from their ability to handle most classes in 1v1, or even 2v1...Reaver even more sometimes...but that doesn't change the fact that they lack escape tools.
Thus I would recommend a Vamp, Valk, Savage, Zerker, Merc, Skald, pet Minstrel, BM (weakest of the light tanks though IMO), any of the 3 Archers (Ranger/Scout are inferior to Hunters), or Assassins (all 3 are good, but NS & Inf are a tad better).
Most Casters are a tad too squishy for soloing, and they probably suffer the most from not having top-level bugs. However, some of the better soloers are probably Sorcs, Theurgs, Mentalists, Eldridges, and perhaps SMs. (Necros can be fun solo too, but are difficult to play.)
GL!
-----signature-----
Windwalker
DAoC Research Wiki:
http://tinyurl.com/35564tf
Minstrel Mentor Column:
http://tinyurl.com/2uog2ur
Coreline 9l1 Ranger & Corlina 11l1 NS 
Currently ~ Corella ~ 3l3 Bard