The 50 HIT from spear dynamo is pretty amazing as mentioned, as with parry, but if you are talking actual damage skills, all of them are outclassed by RK skills. Which is the way it should, as you should be working toward your ultimate 3rd class skills. Bowling Bash can be chained with Ignition Break though, or is useful if you are only going to get Dragon Breath for AOE as DB is fire only. BB will be good for killing the fire immune/resistant monsters in that case. Or get Brandish Spear instead of BB.
im currently a brandish vit knight. bout to rebirth. are you saying im going to have to level up exactly the same way i did before, just using brandish or bowling the whole time and pierce for single targets? or does pierce get replaced by a lord knight spell. im well aware that the 3rd class spells rock, but theres that 1-99 gap to getting there that i have to deal with =p
also i wanna note, that despite its nice low sp cost, im most likely going to bypass getting brandish this time around due to the fact that its bugged to hell. sometimes it does 0 dmg cuz of bug. i think it might have to do with mob being near objects but im not sure. and also it wont cast sometimes despite me spamming the button. overall its a huge pain in the ass and the -defense debuff during it sucks as well. my friend said it was doing 0 dmg cuz i was missing, but i tested it on thiefbugs and was missing on them too which is literally impossible with my 50 dex. just another in a long list of bugs in this game that will never get fixed