Focus is basically for regaining Stamina. As there are some Artis with good Stamina Reg (or -leech), it is not really necessary. It helps to build a new Char though untill you find the right gear.
If you want it for Mana Reg, Meditaion is the better choice - if all of your armor is mediable. The Mana Reg rate of Focus is only half of the Stam Reg and only usefull if you can't yet replace your non-mediable armor.
Yes, you will need Parry for a melee fighter. If you insist having Focus, you may drop Resist for it.
Aside this, it is a pretty solid template and you can do very well with it, unless you want to try Peerless Hunts or Doom or such insane things. If you do, take along another Dexxer (min. 120) for cross-healing. The tougher the monsters you go for, the more properties your gear must have.