I don't think the fee should be destroyed. It would be a much better idea to pay it to Bitcoin miners or XCP holders. No? Maybe I don't understand it well enough.
But yeah 5 xcp seems a bit much.
Destroying the fee
is paying it to XCP holders.
"Lost coins only make everyone elses coins worth slightly more. Think of it as a donation to everyone."
PS: I'd say 1 XCP for new assets. I like round & prime numbers. I'm afraid to see a wave a spam issuances like COKE/CRACK/METH/DILDO/FRENCHGIRL coming from the same guy if you lower it too much...