Previous discussions with 8 string electric bass owners suggest you could expect almost Grand Piano like string tones from the instrument.. and alternative tuning potential one of the deepest and scariest mandolas on the planet..
your reasoning for string course reversal sounds fine for your personal requirements.
But for bridge i'd seriously suggest a fully adjustable electic bass bridge, with independant intonation adjustment for each of the 8 strings; if you can locate one. Anchored to a solid block of wood under the soundboard.