Don't know about Tiki, but Nowi can be reclassed to Manakete once you hit level 30 on that class (or level 20 on any other class). This allows for an infinite loop of Manakete class that allows you to learn stats fast. 

I bet it works the same for Tiki.

As for Counter, it's a skill of the Warrior class, learned at level 15. 

Cool, thanks. I'm at Level 29 94Exp with Tiki, so I assumed I wouldn't need to grind that extra little bit to get the option the change back.

The level 30 classes are pretty good to get stats, since you gain a bit more exp than promoted classes, plus Manaketes and Taguels have good stat caps too. I'm planning to leave Nowi, Nah, Panne, Yarne and Tiki on their respective classes once I finish getting the skills I want for them.

A shame that the Villager class has such poor stat caps, would be cool to leave Donnel on that class and Solo everything with him just having a pot over his head XD.

Yeah, I always recommend with either Manaketes or Taguels, level up to 30 at first, then go about a class changing quest for skills. I recently completed getting both Nah and Tiki some skills and once finished reverted them back to Manaketes. Yarne I went on to be a beast, with a good number of skills, I put on some boots and the only thing he lacks is a reliable answer to ranged attacks, although with Sol he recovers quickly.

Warrior is Donnel's highest stat cap class right? Also, which class is preferable for an all magic avatar; Sorcerer, Sage or good old Grandmaster?

Edit - Left my FeMU in Sorcerer class. The ability to use a forged Nosferatu opens up an extra skill slot.  Anathema, Galeforce, Tomefaire, Armsthrift and Ignis is an amazing combo for a maxed Mag+ Sorc avatar. My forged Thoron hits Nergal for 46x2 and Ignis adds an extra 14 damage .
          
Disregard above strategy for FeMU
Acquire Morgan
Use above strategy on Morgan (exchange forged Nosferatu for forged Aversa's Night) and put FeMU on Sage
???
Profit

Make up your mind!

Oh and I prefer going Dark Flier when wanting to use magics. :P

Rofl, should have said "disregard above strategy for FeMU" XD. 

Dark Fliers have a compound weakness with their Flier class plus low defence. My Warrior Donnel and Bow Knight Inigo, both equipped with Parthias or forged Brave Bows eat Dark Fliers for breakfast .

I prefer a somewhat sturdy, 0-weakness, magic class. With 50 Mag, my FeMU can Staff support anywhere on the map with Catharsis, Rescue, Fortify and Ward so she doesn't have to move at all and if an enemy does manage to break through, she can get an odd kill here and there with forged Thoron.

On the other hand, with 42 def and 46 res, my Sorc Morgan can tank some hits and get free health buffs with forged Aversa's Night.

Slap a Iote's Shield to solve half the problem.

Invest in self healing skills to solve the other half.


And I'm not down with Sorceror's with Nos/Aversa, it just breaks the game.

Iote's Shield/playing smartly make up for them weaknesses, and I believe Warrior's n Bow Knights aren't much for def/res either Mr. double standard. :P  Besides, their def is high enough to where they can't get one rounded by  an equally strong opponent, and Magic seems to be more OP than weapons so if I had to choose one I'd take the higher res. Plus you could also have her equipped with Sol, Renewal, n Pavise, for massive tanking ability. Yeah I'm clearly biased here but still!

Isn't Iote's Shiled a paid DLC item? Plus, that's an extra skill slot that you have to use that could be filled with something more useful. 

How about an Aversa's Night that's almost impossible to break at 49 luck? . Also, I don't see how it breaks the game, at least not more than slapping Lifetaker or any other self healing skill.