Are you hand or machine quilting?
yep on the few inches for batting and backing, I dont measure mine just put it all together then cut off the extra a couple inches around. Mark as much as you need to. I don't think going back to do the hearts later would be a big no-no, but if you are going to hoop each section it might be quicker/easier to do them while your already there instead of going back and re-hooping.. just my thoughts...
Most important, relax and enjoy