From the BJCP Style Guidelines:
American Pale Ale Vital Statistics: OG: 1.045 – 1.060, IBUs: 30 – 45, FG: 1.010 – 1.015, SRM: 5 – 14, ABV: 4.5 – 6.2%.
American Wheat Beer Vital Statistics: OG: 1.040 – 1.055, IBUs: 15 – 30, FG: 1.008 – 1.013, SRM: 3 – 6, ABV: 4 – 5.5%
Your Pale Wheat Ale estimates: OG: 1.069, IBUs: 51.
You're already a little higher than the pale ale style guidelines for both OG and IBU's but the ratio seems the same.
It's almost an Imperial Pale Wheat Ale. ( ;)you've made a new style, perhaps?)
I'd stay closer to what you already have (i.e., I would not bump up to 70 IBUs). It looks like a delicious recipe.
I think its pretty silly to throw in the style guidelines on a 1.070 "wheat beer" with American, German and English hops.
51 BUs is probably a good balance between what you had and what I was suggesting. I make a hoppy wheat beer that is more like a pale ale with an equally matched OG to BU ratio, which is what I was thinking. Then again - I don't think a 1.070 beer with 70 BUs is very bitter. To me thats balanced. YMMV.
What you have now looks about perfect to me. When's the party?