I get the impression from many that a slave is considered to be "better" than a submissive.

A slave does, this, a slave is that, a submissive...well they are just always aspiring to what they haven't and can't obtain - slavehood.

A person who has no limits, no laundry list of things they won't do...hmm. I don't think that is healthy. There should always come a point where a "no" comes in.

Dominant: I am going to tie you. Sub: Yes.
Dominant: I will use you. Sub: Yes.
Dominant: You will jump off a bridge. Sub: NO.

See. It's good to have limits. The person that doesn't have any just jumped off that bridge and splatted everywhere.