What is the point?
1- You have only 3 bars which are maxed easily by just having all spells from two schools.
2- You are talking about ignoring every single other thing the game offer for combat just so you know all spells, once more what is the point?
I still don't see the point, you are locking all schools into one character that can't possibly have enough AP to play around with all spells from four schools.
So uh... it's going to be remarkably difficult not to insult you and the gene pool you sprang from but I'm going to give it a go while I snap into a slim jim. Only the proud memory "The Macho Man" can hold me back from engaging in the ass whooping you so desperately deserve.
First... am I not missing out on so very much by investing so heavily into one character?
No. Why? Because I have TWO characters. The other character, a bow based skill monkey does my loremastering, my lucky charming, my percepting, my sneaking and my crafting. She's also capped out on crossbow and is learning marksman and scoundrel skill.
So she does a ton of damage, as well as being incredibly useful.
But what about "having only 3 skill bars" (which is 30 skills, mind you), I can just hit the K key and bring up the extend menu that has all of my BAJILLIONS of spells. So I just reserve my most useful and frequently used spells for my hotbars.
If I go any further this will devolve into ridiculing you, and I'd rather not become 'that guy' again.
