It’s a question that doesn’t have a definitive answer. I shall now demonstrate this badly through the medium of dubious generalisations and a load of stereotypical bollocks.
Ipwn Orderz wants his sovereign armour and all those lovely orange pixels. It will demonstrate how uber and superior he is. And damn you all, he wants it now, he deserves it and he has put bloody master looter on to prove it... But just in case of problems, worry not, he has an alarm clock ready and waiting. In the meantime, he’s just spotted some Order carebear noob called Nailsinyourface, time to get facejumping and spamming /puke. I is win!
Ipwn is quite happy to have city sieges as regularly as possible. Mythic should get rid of that stupid lock out.
Aragun Alucard doesn’t really care about loot; in fact he’s got more than a slight whiff of the roleplayer about him. Ipwner thinks he smells of beards and sandals, though Aragun wonders how that cretin can smell anything over the stench of stale Lynx deodorant and baked beans. Aragun wants city sieges to be momentous occasions, something rare and unusual that provides epic tales of in-game heroics and last stands. Aragun thinks city sieges once a month sounds about right, ideally served with mead.
Nailsinyourface likes to fight players and sometimes he might visit a dungeon. He’s not that fussed about loot, it’s handy to have, but he knows he’ll get it in time. He just wants to have a nice fight, a few smokes and perhaps a can of Stella Artois or four... Hell, maybe he could try out some halfhearted RPing for some escapism, he’ll just have to bind a button for walk/run toggle and say thee and thou a lot right? If Nailsinyourface is lucky it might even provide some peace from the trouble and strife and her incessant talking. And who in the blue hell is this facerolling twat jumping on my face?
As for city sieges? Well, the campaign is just something to provide some variety, so as long as they’re not every day or anything… Couple of times a week at most seems fair.
Whatever Mythic do (or don't), they’re going to get grief from someone.