4 points in block (up to block runner) are going to make a huge difference. You'll be able to move around without taking really heavy arrow and spell damage. You'll have to switch your shield in and out, but who cares?
That is a very good point! 4 perk points for situational defense and a way of closing with a ranged enemy:
(20) Shield Wall 1 (Novice) -- Blocking is 20% more effective.
(30) Deflect Arrows -- Arrows blocked by shield do no damage.
(50) Elemental Protection -- Blocking with shield reduces fire/frost/shock by 50%
(70) Block Runner -- Move faster with shield raised.
I wonder whether "Deflect Arrows" requires you to time the block, or whether having the shield raised is enough.
I also wonder whether arrows that do no damage can still stagger/paralyze you (perhaps only if you didn't have the shield raised).
Ok... so a build planning to go DW when its perks open up could very reasonably go 1H+shield until then, with the above plan in mind.
Argh so many good things to spend perks on!! (But I love the replayability that this represents...)