Wink [Q] GT-I8910N Kernal and Rom help

Hi there guys and gals. Having a bit of a problem with an S3 Mini exact model is GT-I8910N. Not my first Samsung root as I've done an S2 with dual boot kernel before. My question doesn't relate to which is the best. I am asking for viable ROMs which will reduce battery drain and overclock my cpu. I've used cyanogen on a g2 back in froyo. I've looked into virginity too and the crossover script part confuses me as I've normally just gone through odin and dealt with prepackaged kernels and roms. Which have it all combined. So I am looking for advice on roms but all viable roms not which is best. I can make that choice myself essentially. I'm wanting one with a reduced battery drain. CPU overclock. Bloatware removed and reduced down to as minimal as possible. An explanation of crossover would be greatly appreciated as well as known alternatives. Also am I limited to what types due to the N? I've read there's also an L and an International versions. Assuming that mine is an N as it's in the model number as seen in screenshot. Also is a rollback needed?