Definitely get rid of all the dogs in the park that your Insurance company requires, and also consider tenant discrimination insurance which may come in handy as part of your turnaround.
But whatever activities you perform you should do across all of your tenants - get rid of all the dogs (required by insurance), and make all of them go through a background check prior to renewing their lease. This helps the story around you not being retaliatory and just taking broad strokes to make the park a better place to live. If you’re picking and choosing then the optics are bad for you.
While I believe everything I read on the Internet, you should consult an attorney in your respective state on this too - it will be $500 well spent.
This was a good thread on the dog thing: Dogs...New Rule...Only Dogs Under 30 Pounds...Thanks! - #15 by KurtKelley
Keep us posted!