It depends if you want corals. With most eels and lionfish corals and inverts wouldn't be a good idea. Take a look at some of the corals out there you might change your mind. Ultimately it is up to you but whatever you choose be it fowlr
or full reef do your research and take some time it will help you in the end. As far as more than one anemone in a tank it all depends on what kind you want. I see in your sig that a sebae and a condy. I believe that condy's are more agressive so that might not be a good plan. If you have them separated and they seem to be where they will stay then you will probably be o.k
. If they have clownfish hosting then they are more likely to stay put. Many aquarists have kept more than one anemone with success.