Gucci thinks the ropes are cute, too. 
You could always start with 3 and add more later. If you don't have other fish in there I can't imagine that 1 del, 3 sens and 5 ropes would need more than normal weekly water changes in a 100 gal. The sens stay smaller long term than the other polys in general. Also, if there's decor like plants and dw, I found that my ropes used the height of my taller tank more than the other polys. Just my 2 cents, and I really am not one of those poly pushers - I hate poly carpets. LOL
It's more like 4ft... taller than I would like, but it was a gift. I already have 1 del and 3 sen and I think i would worry about my water quality with 5+ ropes... maybe i am underestimating the power of a sump? I might get a palmas instead.
You could always start with 3 and add more later. If you don't have other fish in there I can't imagine that 1 del, 3 sens and 5 ropes would need more than normal weekly water changes in a 100 gal. The sens stay smaller long term than the other polys in general. Also, if there's decor like plants and dw, I found that my ropes used the height of my taller tank more than the other polys. Just my 2 cents, and I really am not one of those poly pushers - I hate poly carpets. LOL