NXTs as coins... NXTs r not coins, at least the creator of Nxt didn't want them to be coins. They r tokens that grant privileges to support Nxt. Deflation is not much better than inflation, "real" coins should be created on top of Nxt and be issued in quantities that keep their value constant. BCNext understands that this is very arguable, the community should decide if it wants to follow the path showed by him or stick to Bitcoin legacy with unchangeable supply of coins in hope to become rich by doing nothing.
I believe the value of NXT cannot be determined by NXT itself. I would call it external value to stress that issue. If that holds true, a dynamic change in NXT supply might not be possible.
What the best indicators for NXT's external value? MtGox's, BTER's value is not trustworthy. How to determine it then?
FWIW, I could very well live with a constant number of NXT and a slow increase or decrease of its external value.
Another issue, I am concerned with is how to distribute these new NXTs. What mechanism would be choose there?
EDIT: When reading
https://bitcointalksearch.org/topic/transparent-mining-or-what-makes-nxt-a-2nd-generation-currency-364218 one recognizes: "[...] The 2nd scenario can't be applied to Nxt, coz no NXTs exist outside the network. [...]" IMHO this is really important to understand why a constant number of NXTs is the best way.