In my opinion it is impossible to balance a class both for leveling and
T1 content just using skills.
This balance should be achieved by items : when you have a full Tier 0 set with enough sockets, you should be able to beat Tier 1, regardless of your skills (assuming you did not struggle too much in Tier 0)
The major problem right now in Synergies is that this is not true - you need to do a lot of farming before you can get the Tier 1 items from the trash mobs, and only then you can try to beat some bosses. Try, not succeed, because some classes are more advantaged than others..
If you ask me, Synergies is good until the Trolls - then, you need to grind a damn lot, and even then you're not even sure to succeed depending on your class.
In my opinion, Tier 1 needs a major rework regarding balance. But it's a lot of work, one would need to be very dedicated to it to achieve this.
However, back to the skills, the synergies between skills and items could be improved by adding some effects :
- Damage scaling on weapon DPS, and not just on focus and lvl : this is the most obvious one - this way you can truly take advantage of a high DPS weapon
- Adding %elemental damage, like +20% to fire damage. This is the only way to scale properly the flat damage skills. But beware, as this stat might be capped as well..
- Adding %crit damage. Same as %elemental damage - do not work on Damage over Time though
- Health stealing : health management is a major issue in T1. Even if you come with bags of rejuvenation potion, for some classes it's just not enough to survive
- Damage Reflection : this is a very good mechanism to protect yourself from projectiles
- %DR : well, actually since it is capped, and since all chars should have max DR, it only makes you be able to free some sockets..
- Temporary Shield like Engineer's Forcefield, but scaling on another stat than just lvl
And these are the main existing effects that can be used to make your survival better. In my opinion, the worst classes are simply those who do not have enough of these effects.
But Miothan might have a different opinion on this - he is the one who has the most experience with Tier 1 and experiencing with the different classes