The biggest enemy of a crankshaft is deflection, the constant twisting wavelike motion that the crank experiences. RPM is not nearly as destructive.
Deflection is largely dependant on 3 load factors, peak cylinder pressures, rod/stroke ratio, and stroke. The greater the cylinder pressure and stroke, the greater the leverage on the crank(rod journal) the connecting rod has. Rod/stroke ratio also plays a role as the friction on the thrust side of the cylinder wall, and again, the leverage is affected by the rod/stroke ratio. A greater angle (smaller ratio) will be present by using a shorter rod or by increasing the stroke. A reduced angle (larger ratio) will be present with a longer rod or a shorter stroke relatively speaking.
We have exactly a 1.674 rod/stroke ratio, which in the grand scheme of things is a significant angle.
With that said, I think you should be fine on your power levels.