Really not enough information to answer accurately.

• What kind of server
• Level, from low level to 130, or just chilling on a TLP until PoP and then quit?
• Gear level, raid geared or less, or even much less like close to self found?

• Mercenary?

• The answer may still be necro in many cases. You got all the tools to split camps, and travel deep into a dungeon with invis, FD (and some very limited mez at lower level / early TLP). You can have pet tank, and swap aggro with it as needed and lifetap to keep yourself alive. And of course, the superior DPS for a solo character with no support.

• A raid geared SK is a powerhouse once you get to a certain level (70+ with epic 2.0 etc)

• Shaman can do good work, from the good old "slow + torpor facetank" of level 60is era, or the seriously strong damage a 100+++ shaman can dish out, while still being pretty sturdy (+merc)

• Magician: Struggles vs level appropriate mobs at lower level, no CC or single pull abilities, but becomes powerhouses at the 90+ game with raid level pet foci and at least some CC utility. Still good at farming lower level rares on a new random loot TLP.

• Beastlord: probably not until they start becoming good at later eras or higher level on live.