Circuit breakers at the Bus? If you are running a dedicated breaker for each piece of equipment (you are going to need some 2 and 5 amp breakers, and with no AC motor loads I would ask why have a separate circuit for everything?... I would first consider a sub panel to save on all those copper runs (and to prevent leeches, or "other" circuits invading), then yes alternate between the bus (legs), or left side right side in the panel, and try to keep the loads balanced, and the circuit breakers and wires correctly sized for the designed load ("over sized" circuit breakers and wire is not a CURE for anything). Any 220V breaker will already be feeding from both bus bars. Chances are good that your main panel is presenting an unbalanced load now. If a sub panel is separate (downstream) from the main service, through a fused disconnect and a sub panel main breaker, I would consider Isolated Ground Outlets, and possibly (if the current NEC allows) a separate grounding systems for that sub panel, or at least those outlets. A more extreme$$$$$ (but effective) measure would be a complete new service, much like Fremmer did at his house (see his videos). But please consult a Master Electrician, I have not professionally practiced since 1994, and am not familiar with current (lol) code.. The National Fire Protection Assoc. publishes the updated National Electrical Code, and licenses professionals in an attempt to keep us folks from burning, or exploding, things and those we love and cherish.