Kromac2, how to use him

Well, to be honest I picked him simply cause he looks hella cool! Lol! But other than that, I play butcher a lot in Warmachine so I guess I tend to lean towards heavy hitting melee playstyle

Not to push you away from circle but hes got a point. We aren't known for "standing n wanging" (see UFC hopeful Andy Wang about the term). As far as tips, I'm guessing they'd be about the same as the butcher except he gets shot, a lot.

Dirty tricks mainly, since we are not suited for straight punches. Hit and run, hit and retreat with sprint, drag and separate the opponents army. You have to excel at positioning and planning, you cannot commit many mistakes since our forces rely a lot on correct order of activations and sinergy. Our mistakes cost us the game usually. It is a very rewarding faction once you see that you can make it work, but if you want to win just by going for the charge and standing there you won't survive most of the time.

Said that, my only advice, which please understand that I am not an expert and can only talk with the experience of only a few times trying to make lists with Kromac 2, is to focus on a big battlegroup. His spells and feat works better the more beasts you have. Use your shifting stones for healing and fury management, don't try to pull teleport tricks (you are not going to surprise anyone at this point). Use them even as charge blockers to protect your beasts if you need to.

Also I don't know if you have read about the combo with the Woldwrath, but it's a trick that may only work on some situations, and don't forget you won't have any sinergy with the feat.

Another thing you haven't mentioned is what models you have access to. Are you planning to buy everything?

I'm also open to learning new play styles to prevent getting bored using the same strategy over and over. The hit-and-run method seems the most intriguing so far

So, recomendations that are going to be useful in multiple lists:
* Loki. Helps you avoid trading heavies. Works well with several casters.
* The battlebox is a great recomendation. You get a second caster you can start to learn, and three beasts that will frequently end in your army lists.
* Two units of Sentry stones. Still work great on multiple situations and one of the best ways to hide your casters.
* Two blackclad wayfarers. Hunter's mark works great with a melee oriented battlegroup, and the solos have a lot of uses on different lists.

Proxy different units and play with them before buying. Some units won't work with your play style, so only buy the ones you feel comfortable with. There is no "must-buy" unit on Circle in my opinion. Ghetorix is not a must, even with the bond, since it lacks pathfinder, and the Stalker can teach you a better "circle" way of fighting.

Also, I have to say that if you enjoy running this kind of list and don't care a lot about changing the caster, Kaya2 could be your best bet. She is consistent in tournaments and competitive, with better tricks and adaptability than Kromac2.