Even a cheap studio strobe will outdo a hotshoe speedlight
Despite the hoop-la of Strobist propaganda; virtually any studio type strobe will beat out a ***EX series hotshoe type speedlight for the uses you mentioned because:
1. Studio strobes are equipped with modeling lights. You cannot use the ***EX series strobes in the pseudo modeling fashion for any length of time because they will burn out.
2. Studio strobes will work well with light modifiers and will accept many different types. A studio strobe with reflector removed is far-far more efficient when using a softbox. If you put a softbox on a ***EX series speedlight, you are trying to diffuse light that has already been concentrated by a reflector. The studio strobe will not need all sorts of extra accessories in order to work with the light modifiers.
3. Most studio strobes are a LOT MORE POWERFUL than the ***Ex series speedlights.
4. Studio strobes have built-in sockets for mounting on light stands.
5. Studio strobes are equipped with built-in slaves.
6. The studio strobe usually is powered by AC current rather than little AA batteries (However, there are battery powered studio strobes). The AC current maintains a steady fast recycle time rather than the recycle period getting longer and longer as the batteries lose their power.
7. Many excellent studio strobes are a LOT LESS EXPENSIVE than the ***EX series speedlights.
If I wanted to haul gravel for my garden, I guess that I COULD fold down the back seat of a Toyota Corolla, cover it with a tarp and shovel in the gravel. However, this certainly would not be the best way to haul gravel. I would be a LOT BETTER OFF buying a pickup truck which was built for hauling things.