Runes of Magic US / AU

P/W

But if you want it from those 4 choices, I'd say W/P.

It all depends on what kinda of soloing you want to do. If you want to solo well and be able to tank for parties then k/w or k/anything can solo just fine. K/w with good 2h axe though will let you lvl faster. Also if you only want to tank some of the time and dont want to try and pvp as knight main the play as w/k main. Most of the current generation of rom players are simply not cut out for playing knights anymore because the class is very difficult to master in pvp and requires 2 full sets of gear. Perhapes you could provide a little more info seeing those listed can all solo just fine.

Untill knight gets their fix i will not recomend knight main to anyone so for poll reasons i recomend w/k for they can both tank(somewhat) like knight as well as hold their ground against other meele fighters.

Ofcourse the info i just provided comes from a pvper so I am not sure if this helped. I recomend based on the current posts here that you role w/k/p that way you can have k/p k/w w/k w/p p/k p/w. All are good combos with some requiring a bit more skill to play then others.

Soul

I speak from experience, as a 72P/72W/70K. You can solo very well as a P/W up to lvl 60...but you need specialized gear that cannot be used efficiently on your other classes. That being said, however, P/W is a very fun class to play. The easy route is as W/K, no issues there and very straightforward. AS mentioned above K/anything can solo, but warning...it is a dull grind and most people you will find will quest on their other classes and turn in on the K to level it. The same goes for W/P, much like the K it is a dull grind because you are depending on being hit to generate rage as the priest side does not give you any spammable attacks whereas the W/K can spam holy strike and disarmament from their knight side.

Note: The P/W is a hybrid class, commonly known as a Battlemonk. You can search the Priest forum for more info on this specialized class