What do you take photos of? The mirrorless "replacement" for the 7D is the recently announced R7 [0].

The R7 does have a built-in intervalometer, if that's what you mean by taking continuous photos. The other interpretation of continuous photos is holding down the shutter release and taking photos as fast as it can.

Generally, newer cameras do better in low light. Autofocus in low light is improved in the current crop of mirrorless cameras vs DSLRs.

[0] https://www.usa.canon.com/internet/portal/us/home/products/d...