Big aircraft just too big?

I just saw a few video’s of the A380 and that led me to the AN-225. Are these aircraft just too big? The AN-225 looks like it just staggers in to the sky and is on the verge of freezing to halt in mid climb out.

Can you have too much power in something so large? Would the AN-225 benefit from hanging six GE90’s or RR Trent 900’s off it?