I started working on a story about some planeswalkers which I'm not sure if I'll finish / publish, but this is one of the main characters. I based some of his abilities on what happens in his first duel in the story. I know that tokens with abilities / counters are hard to keep track of, but you're unlikely to pull a planeswalker in Limited, and if you have him in your Constructed deck then you can just make sure you have the token cards to represent them. His first ability is made strong to balance out the others that aren't really worth it for the loyalty cost.
Winch, Forest Hermit - 3gg
Planeswalker - Winch
[+1] Put a 1/1 green Treefolk creature token onto the battlefield with "At the beginning of your upkeep, put a +1/+1 counter on this creature."
[-4] Put a 4/4 green Rhino creature token onto the battlefield with "This creature must be blocked if able."
[-8] Each player's life total becomes the number of creatures he or she controls.
[4]
Also - here is a card I posted in FSS. In the original ravnica there were a cycle of artifacts that could be used in any color but got better if you were using the colors of the guild, like
Sunforger 
and
Walking Archive 
. Here is a simic one reflecting how green ramps mana and blue stores it.
Simic ramp artifact - 3
Artifact
T: Add 1 to your mana pool.
gu, T, Sacrifice Simic ramp artifact: Add 5 to your mana pool.
