Question #1- Will we be able to add completely new Perk trees? Cooking, Mysticism, Duel-Wield, etc ?? Will there be a way to invest in these trees aside from using Perk Points?
Question #2 - If someone came up with enough ideas, could they double the number of perks in each tree and give 2 points per level? Some things would be simple, like 10/20/30/etc% on things like light armor. Costing 10x perk points to max instead of 5x.
Idea #1 - Perks determine Health/Magicka/Stamina
Rather than choosing Health, Magicka, Stamina when you level, each perk could provide a boost to these stats. Destruction/Illusion would give +15 Magicka, Restoration would give +5 Magicka/+5 Health, Light Armor +5 Health/+5 Stamina, Heavy Armor +15 Health, etc... Selecting perks with single bonuses would give larger bonuses, but the ones with dual bonuses give the benefit of increasing 2 stats at the same time. Perks could also give % gains to those stats instead of static increases. I would obviously rather have +2% Health than +10 Health.
Idea #2 - Give skills upon spending perk point. Spending a point in Apprentice Destruction magic could come with one apprentice level destruction skill.
Idea #3 - Mastering a perk tree. Applying 8 or more points to the same tree gives you a buff of some sort in that area. Mastering 100% of the perks within a tree gives an even larger buff. Alternatively, putting 2 points in all trees could give a "jack of all trades +2% health/magicka/stamina regen buff" and putting 5+ points in all categories gives a larger buff.
