The only Windows Mobile devices that I am aware of that are not cellphones too are the IPAQ 110 and the IPAq 210. I
reviewed the IPAQ 110 and found it to be a decent pocket pc. I have not had a chance to work with the IPAQ 210, but there are
several threads here that discuss the strengths and weaknesses of this device.
Most all the newer windows mobile devices (those that run the WM6.x OS) do not include an IR port, so you won't be able to use any of the hardware you currently use with the 2210 that relies on IR as the connection. I also wonder if your Margi Presenter Card will work with newer devices - the transition from windows mobile 2003 to WM5.0 was a dramatic change and was not necessarily backward compatible. Between the IPAQ 110 and the IPAQ 210, the IPAQ 210 is the only one that accommodates a CF card.
Both of these devices include a WIFI radio, but you'd need to purchase an external GPS solutions (connect via Bluetooth).
If you are running out of memory on the h2210, why not just get a larger SD or CF card for it and install your applications there?