Well you certainly seem to have a lot of apps installed for a RPi I’d say yes ;D But maybe that’s fine (at least the graphs you showed do not worry me, but I’m not a monitoring expert).
Imho you should definitely look into the swap thing, e.g. if you run free -h and have 0 swap, that’s kinda problematic.
Have you tried to set it up with something like this ? (adapted from here)
dd if=/dev/zero of=/swapfile bs=1024 count=1048576
mkswap /swapfile
swapon /swapfile
echo "/swapfile swap swap defaults 0 0" > /etc/fstab
Not sure why you get the Input/Output error … I usually see those kind of errors when disks are dying, but maybe here it’s just due to the file not being properly set up :s