Building up a modified road bike for my older self. It has a Ultegra 2 x 10 speed group set. Was planning on making use of the group set with existing 8 speed shifters and cassette I already have that will fit the alt handlebar set up that works for me. Please note that drop bars make my hands go numb after about an hour now a days and have tried all the solutions on here and the rest of the internet. Keeping the drop bars and brifters is not possible.

OK as previously mentioned. Was going to just use the group set along with a new 10 speed chain along with the 2 x 8 flat bar road shifters and 8 speed cassette to replicate another bike this has already been done to. Yes it works. I can do 16miles an hour for 42 miles on this set up with out arm/wrist/hand numbness. Was wondering if there was enough advantage to justify spending about another $120.00(not rich) to get new shifters and cassette to go 2 x 10. Dose having the same range but with closer steps between gears help us as we lose watts(muscle/power) as we age?