Another vote on 14-140 f/3.5-5.6 (mk-I or mk-II). Its versatile zoom range which can reduce a lot of lens swapping, sharp, good contrast, only 265g in weight... It might cost a little more than the O 14-150, but the better performance, not to mention IS for non IBIS GF/G100, DUAL IS for GXs and DUAL IS 2 for Gs & GHs, it is a no brainer for Panny bodies.
Source: Extract from DXOMark
For ultra portability the 70g 12-32 f/3.5-5.6 should be it. Low cost, toiny such that will never be a burden to carry it as spare, reasonably sharp...
For a little longer reaching, the 12-60 f/3.5-5.6. Never under estimate this low cost lens. As per the lab test by OpticalLimit, it is actually not very bad vs its bigger brother the PL12-60 /2.8-4, even can hold a good position vs the highly recommended 12-100 f/4 or the 12-45 f/4:
Source: Extract from OpticalLimit
My analysis on 12-60 vs PL12-60, O12-100 & O12-45 is as below:
Source: OpticalLimit
For the longer end, the 45-150 f/4-5.6 should also be a good option among its class:
Source: DXOMark
The low cost Panny M43 lenses of my choices.