I don't know if this helps.....
I have an N800, and all of the symbols you mention are available from the soft keyboard. I presume the N810 also has the soft keyboard in addition to the hardware KB.
for iii, why not just get a "travel" access point?
for iv, I use bluetooth PAN with my AT&T 8525 pocket PC. Works fine.
for v, there are adapters available, but the ones I have seen go the "wrong way", i.e. from the big USB plug to db-9.
I can't help with vi

Just in summary, I use the N810 for WI-FI administration - mostly to find rogue APs and to help people connect to the network - kismet is very valuable but a little finicky - there is a whole thread devoted to it here. nmap also works well. Overall, the N800 is the most valuable pocket sized administration tool I've used, and I've tried a LOT of them :=)

HTH

Walt