Get the spokes tensioned sooner rather than later.
That will make a major difference in their life.
Rear is most important, since it carries more weight and undergoes the torque from pedaling.
Think of it as having 1/2 the spokes trying to "unwind" with every stroke, while the other 1/2 are getting "stretched".
Equal tension helps them to share the stresses more equally.

BTW- The RM-30 hubs are available online for about $20, so they aren't the highest quality.
I've actually built 3 wheels this Winter using them, with the expectation they will be serviced rather frequently.
New bearings and grease are about $1.25?