Block & Crank power handling

[1988GTU]

You have to turn the rpm's up though! Everything gets stressed at that point.

[ALLTRBO]

AaronGTR,
I'm not quite sure how that works either but I'll be reading up on it more, I'm sure there's a reasonably detailed explanation or theory somewhere around. I do know that it seems to be true though, because in addition to the article above I've known a few other people to build various engines with high rod/stroke ratios and they're running goodly amounts of boost on 93 compared to similar combos with stock r/s ratios.

1988GTU,
Not necessarily so. If you're staying near a given displacement with the rest of the specs identical then it doesn't matter much. While you'll be able to rev higher you won't really need to. The shorter stroke/longer rod engine might make more power up top, but in reality the powerbands will be relatively close.
For example: a stock 3100 is a 3135cc and the aforementioned .020 over 3400/2.8 is a 3063cc (close enough to each other).

Now if you take a 3400 (3350cc) and do nothing other than destroke it to make a 3063 (w/.020 over) then you'll have to rev it a similar amount higher to make a similar horsepower curve (3350/3063 = 1.094. 1.094 x 6000rpm = 6564rpm). The 3400 will have more torque and make it at a lower rpm, but the HP will be close between the two. This is all considering that everything else stays the same. That is: heads, cam, intake, exhaust, compression, etc.

Now, while increased RPM does stress a bottom end more, a shorter stroke and higher r/s ratio goes easier on a bottom end. I don't know if they balance out or if one stressor is more prominent than the other, but you have to take that into account.
As for the valvetrain, well, you're right there. The usual required mods apply for a given rise in RPM.
Aside from the valvetrain (which isn't much of an issue in this case), the 3063 will be more rev happy than the 3400.