I have jesel 1.55 rockers. I would like to move up to the 1.7 rockers but thats out of the budget right now.
I highly recommend buying a copy of PipeMax so you can run some dyno simulations. Or look around and pick a different SW package but find something that you trust. $100 for a dyno package can save you a lot of money down the road. Or call around and talk to some cam guys and engine builders. I'm pretty sure they'll all tell you the same thing.
Based on my own experience I'll say that you need at least a 1.70 intake rocker arm and probably more like a 1.80 rocker arm on that engine to wake it up. I learned this lesson a few years back after working with Jones Cams on a project. I switched my EZ heads over to 1.85/1.70 rocker arms and added a ton of power. The 1.50 rocker arms just can't get the valves open fast enough for a big race engine with smallish cylinder heads.
One issue with the big rocker arm ratio is that you'll run into valve to piston clearance problems so you have to watch that. The aggressive valve train will also be more demanding on valve springs.
Spend your money on rocker arms and camshaft rather than bigger valves. I think you'll get a better payback.