I mentioned that, mushrooms are a great alternative. I love my anemone(s), though. I will not say anemones are badbecause they are awesome. I've had clowns host in star polyps before. They are really not that picky.
Usually anemones will not eat a clown, especially if you get an anemone that is a natural host to it. The chances are unlikely that a clown hosting anemone will hurt any fish, especially a clown, but it has happened before. Make sure it is a pacific anemone, not atlantic. Make sure it host percs in the wild. If you are planning on a lot of other fish, especially vulnerable fish, stear towards the shrooms. But since the tank is mainly clowns with a couple others, choose whatever you'd like. Just make sure the tank is fully cycled and ready for an anemone. Also leave lots of spce away from the powerheads, filters, pumps, etc. so that the anemone doesn't decide to move itself into any of the above. Safest bet, shrooms, but I can't say I made a bad choice with my RBTA. Might be a good idea to start with a hairy shroom and when tank established, then try an anemone. Also, when my first one died(domino damsel started eating parts of it), nothing else died in my tank. Bubble tips are a fairly good anemone to start with, but watch their movement as they like to find their own spot for a day and then move somewhere else tomorrow, at least mine does.