Makehuman itself was never designed or intended to be used as the prime rendering platform import it into blender for hi res rendering period as we are not going to spend an other two years coding a render engine into makehuman.
Enjoy the Choice
my box::HP Envy i5-6400 @2Q70GHzx4 8 Gb ram/1 Tb(Win10 64)/3 Tb Mint 19.2/GTX745 4Gb acer S243HL K222HQL Q8200/Asus P5QDLX/8 Gb ram/WD 2Tb 2-500 G HD/GF GT640 2Gb Mint 17.3 64 bit Win 10 32 bit acer and Lenovo Ideapad 320-15ABR Win 10/Mint 19
Also be aware of the sample count when upscaling a render. The render time can increase by a lot with higher resolution and along with a high sample count. You could do a high resolution render with a lower sample count to improve render time. Conversely you can do the inverse of the aforementioned method. It's only a suggestion and can be used at one's discretion.