that is what I am referring to... you have the option to symbolize... but to combine into one raster, then you have to physically put them together, which is going to produce new numbers and ultimately change your symbology... so what is it you want to do? produce bottom layer A modified by 50% of top layer B? (that is the raster calculator methods I was referring to)
Your image looks fine the way it is... why do you want to make it into one layer? to show somewhere else? screen grab it?