"damage with weapons and the level of armor he would be able to wear." is one problem in and of itself, but let's gloss over that for now - you seem to be missing the implications. Might is +3% to damage. Always. Even with healing spells. It's always the statistic that influences the endurace shift you're going to cause and it always influences it in the same way (well... More or less, Obsidian still has some work to do for the abstraction to work 100%, but they're getting there.)
No. Strength would also influence your Mage's damage with weapons and the level of armor he would be able to wear. If you want to be able to fight back when something engages you in melee, put a few points in strength.
Now... What about Paladin whose meele attacks may be semi-magical? Does the damage buff get split between Strength and Intelligence? What about other abilities of other characters? What about wizard spells that summon weapons? Is the weapon damage fixed? Which abilities and spells are considered intelligence-based, strength-based or combination thereof? Can I tell that at a glance without remembering descriptions for dozens of abilities? To make these work, you're going to have to come up with more "ifs" for your system.
There's your advantage of clearly laid-out rules right at the base level of attributes. The more exceptions, limiters and modifiers you add, the more confusing is your system going to become down the line for any reasonably complex system.
Edited by Fenixp, 20 April 2017 - 10:23 AM.