Not really. The charges and currents in a flash chip don't interfere with each other for the same reasons that they don't in any other chip. There's a minimum distance you have to keep things apart but luckily it gets smaller every process node. Heat would be a problem if it was like a processor but you're generally only reading from or writing to one part of the chip at a time so heat isn't a particular concern compared to a processor or DRAM.