Sorry, this is kind of long...

My house was built in the late 60s and I have noticed several odd things. One of them is the wiring in my combination laundry room & 3/4 bath, which I have discovered during a recent basic remodel (most walls have not been opened). Here is how it WAS wired:

15 amp circuit, feeding receptacle for washing machine, single recessed light, vanity light, two recessed lights in adjacent family room, and a light in an adjacent utility room. There is one GFCI-proteted wall receptacle in the room, which is on a circuit also feeding receptacles in the family room. The wiring from the panel to the receptacle is 12-gauge, while the wiring feeding the light fixtures was 14 (hence the 15 amp breaker, I suspect this was originally a 20-amp circuit as I have found many cases of lights being fed with 14-gauge wire off receptacles wired with 12-gauge on a 20-amp circuit. I have split some when possible, or replaced with a 15-amp breaker in some cases).

I removed the old lights in this room and ran a new circuit (20 AMP) that now feeds a new GFCI outlet near a pedestal sink (previously there was no outlet near the sink), a new GFCI-protected exhaust fan located over the shower, a new recessed light, and a new vanity light.

This leaves the existing (and almost never used) GFCI wall outlet. This wall was not opened, and it would have been a PITA to move this to the new circuit, it will be staying as is.

Then there is the original laundry room circuit. Now all that is left on it is a duplex receptacle over the washer, two recessed lights in the adjacent family room, and the utility room light. As I mentioned 12-gauge wire feeds this receptacle and then two 14-gauge wires leave the box. The one that used to feed the old laundry room lighting is now terminated on both ends (one end in the box with the receptacle, the other in a new round metal box in an accessible location). The other wire leaving the box feeds the family room and utility room lights.

Now I know some of the legacy wiring is not to code (I am specifically talking about the three lights that are on the same circuit as the washer) so please no code Nazi lectures. I am trying to decide how much trouble I should go through to bring more of it into compliance.

I can run a new wire from the panel to the new round box I mentioned above without too much trouble, so I could use the now abandoned wire to feed a new circuit to the box with the receptacle and take the family room and utility room lights off the old circuit and put them on the new circuit. Then the only thing left on the original circuit is the receptacle for the washer. I could change this to a 20-amp breaker and receptacle if I wanted, since all of the lighting on 14-gauge wire has been removed from the circuit.

Now I am trying to decide if it is worth the trouble of adding a new circuit to power three light bulbs just because code says they shouldn't be on the same circuit as my washing machine. It isn't too difficult to do since I can make use of an abandoned wire already in the wall, but it hasn't been a problem (and now there are two fewer lights on this circuit so in theory the situation is "better").

Should I do it, or leave it as is.