<< I am wondering if I should bother installing a sump pump in the basement
while I am at it, or if the above waterproofing will suffice. >>
Depends on your local geology. If nobody for miles around has a sump pump,
then, no. If your location is on top of a hill of glacial till then, no. If you
have low rainfall rates then, no. Some serious local research will give you the
data to make a sound judgement. Good luck.