In general, ethanol is a better solvent than isopropanol, but not as good as methanol for some things. I wonder if the reason IPA seems to be used more in electronics has something to do with the solubility of rosin flux.
Ethanol is probably a little safer to use, after all people have been drinking it for thousands of years, whereas methanol is classified as a poison and will cause blindness or death if consumed and isopropanol will make you extremely sick at best. Warning, do not drink denatured ethanol, they put a small amount of other solvents in it to make it undrinkable, otherwise it would have to be taxed as liquor.
The plastics used for electronic parts are almost always "thermoset" types such as nylon, polypropylene, polyethylene, etc. These are not affected by solvents much, if at all. Others like ABS and polystyrene however, are thermoplastic and will dissolve in the active solvents such as acetone, MEK, etc.