Adrian, I expect your gut feel may be right, how big are the risks? Can it make more sense to reduce the par, or does the land not allow for that?
Personally, I am not a fan of multiple P5's and P3's in a row, unless they are of really high quality. If you can pull off balance and rhythm in the design, and it doesn't feel all over the place, then it may work - but what is the cost if it doesn't?