Yes, drop bars. Although my wife's old bike had the 90 degree add ons and those helped as well. You need to be able to move the hands around a lot to reduce stress. Drop bars are good even if you never ride in the lower position simply because the offer a lot of alternatives for hand placement.

Regarding the straps, the full on wrist braces worn at night really do help. What I was referring to as being only minimally effective were the smaller single strap braces, although I do wear at times when riding and if you're having a sore day they relieve a bit of the pain, so I don't mean to dismiss them entirely.