1a. Adding a swapfile on the card:
sudo su
cd /media/disk
dd if=/dev/zero of=swapfile bs=1M count=1024
mkswap swapfile
swapon swapfile
This will create a 1GB swap file, format and activate it. "free -m" will list the available swap space then. This will not persist after a reboot unless configured in /etc/fstab. If you want to specify a different size in megabytes, assimilate "count=XYZ" as desired; i.e. specifying "count=2048" will create a 2048 MB file. This won't work on FAT. As most cards ship with it, you have to reformat, I use ext3.
So far, with a 512MB swapfile, I haven't noticed any performance improvements when starting up individual applications as they fit in the RAM anyway. However, multitasking is much better now. I can have Firefox, Thunderbird, two instances of OpenOffice, The GIMP, DOSBox and a terminal open at a time and work comfortably.
dphys-swapfile (available in the repo) may also be helpful as it dynamically creates, resizes and activates a swap file as it sees fit. The default config needs to be modified but it looks quite handy.
1b. Moving /home over to the card is possible but I'd first make sure udev will not get in the way.
2. What exactly are you attempting to remove (package/file names)?
3. The mini USB connector is a full USB port, with host capability. In other words, it is just another USB port but you need an adaptor to use it (or find peripherals with a mini USB port, e.g. Sony offers a mouse that plugs right into it).
4. No idea, I don't use the touchscreen. I use the optical mouse replacement exclusively.