I think you should not worry. The Act.Mon. info that is really important are:
Memory pressure. Yellow and green means no worries.
Wired memory, 1.52GB: The amount of "absolute" memory used by system and apps. (The 'App Memory' is memory that is in use, but can be released if needed.) So, you could in effect have had 4GB RAM on your MBP, and you'd still be OK. I'm pretty sure if you summed up the whole memory column of your running processes, you'd get… 1.52GB.
Swap used, 0: Means it has not been necessary, since last boot, to use the internal drive to lighten any overload of the memory.)
Macs use memory when it's available, that's maybe the reason you mentioned seeing lower numbers on a previous mac. I'm guessing that was a 8GB configuration. If you had 32GB, you would have seen a even higher 'Memory used' number with the same stuff running.