Ok so as for block strings I like 1221 the best. If people try to dash in it sometimes hits towards the end as its range is deceptive. But on block it gives you pushback. You don't always want to be right up on someone. So after 1221 I'll either do shoulder, dash in for f3 pressure, lightning if they sit back, or sit back and axe if they approach.
The axe hits if they try to dash in and attack or jump, if they try to duck shoulder you can dash in f3 or lightning, sometimes shoulder keeps them blocking once they respect the other options.
As for other strings I like f312, 114, and b1111.
F312 keeps me close and let's me jump for crossover since its neutral on block or d3 axe.
114 sets up eh lightning very well on hit. It also sets you up for f3 at the perfect range. Plus 11 on hit gives you time to dash in for another string.
B1 is great because of its range. Use it for wiff punishes when spacing out your opponent. Plus it builds great meter due to its many hits on block and if they let go of block early you can link to axe for a combo.
As for making shoulder less duckable, be more patient and if they just sit there and crouch, dash in and out to make them uncomfortable, throw arrows or lightnings out randomly. They will eventually jump when they expect a lightning then AA with 1 or axe and start again.
He is a high low character also. His d3 is plus ten on crouch hit. It they are going to stand block you have d4 all day as well as shoulder all day. Don't forget to grab them. They have to duck anyways to avoid shoulder so when they do start lightning or block strings. Nw isn't all about the shoulder.