I use the Bank of America platform primarily (with some occasional churns for some sign up bonuses). The 3/2/1 card allows you to earn 3% back on a category of your choosing (gas, online shopping, dining, travel, drug stores, or home improvement), 2% back at grocery stores, and 1% on everything else. I pair that with the travel rewards card that gives me 1.5% back on everything. These come with no annual fee.
While on the surface these cards don't look that great, you get a 75% boost to the rewards if you have $100k in combined Bank of America and Merill Edge (their brokerage house) accounts. So after the boost, I get 5.25% on online shopping (my category choice), 3.5% on dining, and 2.63% back on everything else. All with no annual fee. I think their platform is extremely underrated for those that have the ability to take advantage of the boost. In addition to all of that if you have the $100k in combined accounts, you get a host of other benefits, including 100 free trades per month, no ATM fees, savings rate boosters, etc. While I wouldn't recommend keeping a savings account as their rate is pretty abysmal, if you have enough investments to move over there to take advantage of their preferred rewards program and credit card program, I think it is a good option.