and is accepted is fewer places. Visa and MC are the most widely accepted. Discover pays the best dividends and is accepted at most places (carry a MC or Visa as a backup).
Discover pays 1-2% depending on your credit rating. Just getting started expect 1%.
Airline points are not worth the effort as the airlines keep changing their plans and points expire - cash doesn’t expire.
Hotel points are easier to use than airline points and are generally easier to add to, but be careful as the hotel chains keep changing their plans too.
I use a Hilton Honors Visa as my back up for the Discover. And a Citibank Priority One (Holiday Inn chain) Visa as my business card.
Look at the fine print of any card. There is no reason you should pay the lender for the use of their card - there are too many choices to have to do that. Make sure you pay the balance in full each month and on time and you’ll never have to worry about interest rates.