Just a thought about a portable base for your sewing machine: the way the head sits now, in the table, you have a flat bed working space, and very likely close to an ergonomic position for your height. If you put the machine in a base, on top of a table, you will lose your flatbed working surface (more drag from the fabric ensues) and may feel as if your hands are "perched" uncomfortably at a weird height and angle. You may want to try it as is before making major changes.