i like changing it up every now and then. sometimes i work like with like (aka: back, biceps/ chest, triceps/, etc). otherwise when i do a four day split it usually looks like:
Mon - chest, biceps
Tues - total legs, abs
Thurs - shoulders, traps, tris
Fri - back, forearms, abs
i also alternate btw doing a four day split and a three day total body lift combining HIT/HST principles. works for me.
your split looks ok. personally, i'd work hams w/ legs since youre generally hitting them anyway with squats and deadlifts. you really don't need to work calves twice a week, though it's ok if you prefer. the only problem i see is that you're working biceps and back one after the other. since back incorporates a lot of biceps - and your bi's are likely to be sore following your thurs lift - you might risk overtraining them on back day. consider switching biceps to monday, which would give them enough rest time for your fri back lift. then you'll have the weekend to rest.