There should be improvements in most areas, including your wireless,
depending on what sort of wireless card you have. Is it natively
supported, or do you have to run the windoze driver under ndiswrapper or
something of the sort?

If you're happy with it, and there's no change in the wifi for you,
there's certainly no need to rush into an upgrade. If it were me, I'd
boot up with the 10.04 live cd and see how everything works, just for kicks.

FWIW 10.04 will be supported longer.