Not true that you need big heads and cam just with stock heads and 268 cam you'll make peak around 4000rpm and be done before 5000rpm it be more like a truck engine, but run a 2.94:1 rear gear and you'll still have an usable powerband.
Well yeah........kind of , sort of.
Then you get into the " why would you ? " question.
More inches want more air to make more power.
If you would be satisfied with the same power at lower r.p.m. , then this is an option.
But strokers like duration , and air in and out = h.p.
On the other question , a longer rod requires a custom piston in most cases......" shelf " pistons are available for 3.58 , 3.79 and 4.00 " strokes with either a 6' or 6.123" rod if you shop around. Basically , if someone is offering a kit for a given stroke , they use a fairly common piston.
Going with a longer rod isn't worth the effort or cost in most cases.....especially with longer strokes.
You get into a tight ring package , oil ring supports , piston rock and a host of other issues that significantly reduce engine longevity.