That's a shame, I found Ziggurat to be a really fun game but it does require a bit of practice and it isn't one of those games you can sink hours into but it fun to bring up every now and then. BTW, there are items in Ziggurat, amulets specifically that give abilities you can activate and there most definitely are perks, that's the cards you mentioned.
Just to let you know, both apprentice characters (Argo and Corina) have max spell, staff and alchemy mana at 100. The only difference between the two characters is Corina's wand has a faster firing rate. The first unlocked character (Kraz) that you mentioned, the game actually does tell you what his description means. Kraz's health is 100, max spell, staff and alchemy mana are 50 and starts with Wand Mastery 5 and Wand Link 5 perks which increase wand attack rate and wand mana recharge rate respectively. The problem is you have to be playing the character to see this information, you can't see it during the character selection screen (which you really should).
Also the game doesn't really need to explain the difference between wands, spells, staves and alchemy as you'll figure it out after a few minutes playing with the weapon. Did anyone really need an explanation of what the weapons did in Heretic or Hexen? No, because you could use the weapon a few times and find for for yourself.
Part of playing this game is managing your mana, mentally tracking multiple enemies, knowing when to apply pressure, when and how to evade etc all on fly. All the information you need is presented to you to do this, question is can you process it quick enough? If you are burning through all your mana and getting swamped by the enemy, you're doing it wrong. I could explain further but context is required (ie, what weapons you have, what enemies you're dealing with, room layout etc).
Also don't know what you mean about player movement being slow? Movement is actually very fast like in classic FPS games (Doom, Heretic, Duke 3D etc). It might seem slow because the rooms are really large. The PC movement in Unreal 2 or a console modern military shooter, that THAT'S SLOW.
Maybe I'll try out Tower of Guns sometime and see how it compares.