Thank you, Xzavier247 for your encouragement and advice. The yellow-ribbon plant is not truly an aquatic plant, as both you and I believe Ninjouzata have pointed out. It is a type of dracena that can grow in an aquatic environment, and supposedly will eventually grow and climb right out of the top of the tank. But I'll trim them when/if that happens. Or get rid of them if they die. For now I like how they look, and they seem healthy.
I have been closely monitoring the new additions to the tank, and as much as I hate to change it yet again, I'm pretty sure I need to remove the clowns. I love them, my tank is big enough for them, but they are hyper and they are spooking my discus. The "discus ball" i had hoped to achieve has yet to materialize, the new guys are still very shy and skittish, and one of my original discus is also being aggressive with them. It's all too much for them I think. Anyway, out go the clowns; I will bring them to my new lfs tomorrow and offer them for free. Shame. These guys were kinda pricey, but maybe I can generate some good will with the guy at my new lfs. He did give me a killer deal on the discus i got from him yesterday.
SO.....how on Earth am I going to deal with the MTS problem? Not sure. Been doing a lot of reading on the subject. Most things I've read about snail traps and cucumber baiting seems hit-or-miss, and my own experience with baiting and removing has fallen far short of the mark. I will not use chemicals, not even hydrogen peroxide. Many people say that the real problem is over-feeding when it comes to MTS infestation. If there's no food for them, their population declines to barely noticeable levels. Others suggest 10 or 20 assassin snails, and while i don't want to trade one snail infestation for another, I've read that once the assassin snails wipe out the MT's, they die off due to lack of food. Which sounds okay to me i guess. But maybe the assassin and trumpet snail populations will both continue on, but at an acceptable MTS population level.
In my recent experience and in reading materials one key concept remains at center stage - balance. If my tank were properly balanced, algae problems and snail problems would just go away, with very little effort on my part. I need to achieve that balance in my tank, and while I know I still have a long way to go, I feel sure that I am heading in the right direction.