Usually, playing a fighter is just not my style. Hack, slash, more hack, more slash, and someone dies. Well, this is not the case with the fighter here, as I was happy to find out yesterday.
Yes, it does include a lot of h&s. Aside of that, you also have crowd control abilities. On these first levels these are abilities that can stun or knockback. Both of these can be very handy if you find yourself cornered and attacked by several monsters at once. (Ever seen four or more 'h' monsters speeding up and running towards you, when you are standing in the middle of a huge room? It is frightening.)

My choice of skills included the following (and I try to keep spoilers low here):
Shield pummel: Can stun the enemy and offers decent damage.
Repulse: Knocks back and dazes your attackers (the ones that stand next to you). It won't work if someone or something is behind the monster though, so the usage is somewhat limited.
Rush: Very useful for ranged attackers (archers and mages both), partly because you move there in an instant, but the daze effect is also very handy.
Riposte: Attacking enemies for free is always a good idea. Especially when you are surrounded.
Overpower: An effective attack with an additional chance of knockback. Very useful.

So I've just unlocked the summoner yesterday, and decided to give it a go. As my previous experiences with Tome4 were only limited to getting a warrior up to lvl 11, I'd say I had no idea how hard it will be.. but I was able to survive the first 6 levels, and kill the boss in the first dungeon. This post is just a very simple strategy guide for those early levels for others who would like to try this class.

Level 1: Run!
The first rule of survival is simple: summon and run. Your main goal here is to get some weapon, which can be accomplished in two ways: one is to find a suitable weapon (it helps if you raise your str to 11), the other one is to collect enough useless stuff to sell them and buy one in the shop. For this, you need to explore the wilderness, but - because your are pretty squishy yet - the best possible tactic is to stay close to the entrance and flee if needed.
If you learn the turtle - which is a very good idea to do, btw - you can try to hold back single monsters. Summon it, wait until the monster starts to attack it, then run away a few steps. When the turtle disappears, summon your ranged pet a few steps away from the monster, and move again. Then the same with your wolf, next to the monster. You can repeat this until the monster dies or until your equilibrium prevents you from summoning. In that case (and the same for several monsters coming towards you at once) run to the entrance and leave the area.

Level 1-3: Deal damage
After you found at least one decent weapon, you can change your tactics. First of all, improve your ranged pet, so it will deal decent damage, and maybe also your turtle, so it will stay for a longer period of time. Now you can team with your pet: You can tank for your ranged pet, you can work together with your melee pet or you can deal damage while your turtle holds back the enemy. The damage you can deal together is now enough to kill a group of enemies - if they come one after another. Never stay in the open, always get to some corridor where you and your pet can hit, but there is space only for one enemy. A useful tip here: if you don't see any space where you can summon your pet, try to summon it on top the monster. If there is an open space next to it, your pet will appear there, even if it is behind the monster or outside of your LoS.

Level 3: Kill the troll
Now you should be able to kill that first boss. It helps if your cunning is 20+, but not required. Probably the easiest way is to run around and use your turtle to hinder it and your ranged pet to damage it.

All in all, the first levels of the summoners are not easy, but doable with a little patience. On the other hand, it's good fun, I really enjoyed it, and I suspect that the summoner can become really powerful after some levelling.