Current group setup with friends. Cleric SK Enchanter I'm trying to decide which class to roll for DPS on the new Selo's server. Beastlord - Mediocre dmg, jack of all trade. Monk - Overpopulated on TLP, I don't want to pull. Rogue - Bad dmg from what I've read? Ranger - Solid dmg only when you get Bows & AAs? Overpopulated on TLP? Magician - Solid dmg, overpopulated on TLP Necromancer - same spell line as SK? Wizard - rare, needed in raids. But not great group dmg? versus raid dmg.
Necro is nice because you can FD when things go bad and rez the Cleric, not to mention feeding mana when needed. That said, Mage is good for CoH if friends show up late. Wizzy ports are okay, but less important with Selo's expansion timeline.
Where are you reading that? Nothing could be further from the truth, rogues have insane damage output. Just ask anyone in a raid guild, rogues are on top of the DPS parses. (for the record, I don't have a rogue, so I'm not biased, I just know what I've seen over 20 years.) Based on your choices, I'd go Mage myself.
Mage is really nice. Add the pet/chanter haste for more dps. Decent off tank if you guys need that also. Summon toys, mods, food/water and more. Necro's are good but often times, the dots don't do the work that makes them useful unless the mobs take a while to die. Most stuff you kill around your lvl will be dead before the dot ticks 3 times.
If you're playing with your friends, it probably won't really matter what you choose. If you plan on raiding, it may make certain classes more desirable. I do have to wonder who will be pulling in your group if not you? If it's the SK then pulling will be a moot point. From what I have read, Beasts won't become too powerful until a few more expansions, if you're looking for more immediate power. Rogues, especially with PoP weapons, are really strong. I think when people say Rogues are weak they mean during Classic and Kunark for the most part, and it's mainly because monk HtH damage blows everyone else out of the water. Speaking of Monks, you can offtank in a pinch if the SK gets in over his head or is feeling lazy. Most of those classes are overpopulated because of how powerful they are. Wizards are fine in groups, again I think it's being overshadowed by mages and their pets. Once you hit the 40s/50s you probably get tells to join a guild if you know what you are doing.
Enchanters can pull fairly well too, plus I've seen some of them do some amazing things with Rune Tanking when they know what they're doing.