Your lighting set up will suffice for a BTA, although I'd aim to have it situated more towards the middle than at the bottom. Besides, the BTA may end up moving on you anyway if it doesn't like where you've placed it, so be prepared for that eventuality. From my experience, BTAs prefer a slight hollow in the rockwork for their foot. Other than one incident, during the over two years I've had my GBTA, it hasn't moved more than an inch or two. It's in a fair sized depression in a rock just under half way up. I run four T5 HO 54 watt lights for most of the day, switching to 2 x 250 watt MH during the mid day period. The MH lights are a relatively recent thing, I ran strictly T5s for at least two years with the BTA and it did fine. I do think it's doing better now with the MH addition, but the fact that I switched to RODI from treated tap water could also have a lot to do with that.
Another point to be aware of, especially with your DSB, if you have your anemone too low, your Maroon female is likely going to make a very large hole in the sand bed beneath it. Mine does this even though the anemone is close to 5 inches above the sand bed. She's taken my 4 inch sand bed down to bare bottom in one location. It's what they do, she will use her tail to fan the sand bed under the hosting anemone.