I'm often surprised by the plant's people to choose for their hanging baskets. Many of these plants would work so much better if you were looking down at them instead of up, which is usually the vantage point you have when looking at a hanging basket.
I recently saw a professional video done on how to plant a hanging basket and couldn't believe my eyes. They stuck a bunch up moms in a hanging planter and called it a day. Now I don't have anything against moms, but they are just about the last plant I would put on their own in hanging baskets.
Moms are tall, upright plants. Their beauty is all in their flowers, which face up. The leaves and stems are, well, not to put too fine a point on it, ugly. If you put a mom in a hanging basket, chances are that the leaves will be at eye level or even above. So you would be looking at stems, leaves and the undersides of flowers, and would miss the prettiest part of the plant altogether.
There are a couple of ways to avoid this. First, figure out where you are going to hang your basket. If it's really high up, you might want to consider just using just plants that will fall over the sides, sometimes called spillers, because that is what you are going to be looking at. Some of my favorite sellers are:
Hanging baskets often look great with a single type of plant, but mixed baskets can be beautiful too. I will often buy a pre-made basket of mixed calibrachoa (aka million bells). However, I will almost always take it out of its nursery pot, as I find that most are root bound when you buy them -- the roots have often displaced almost all the soil, so the pots dry out in a nanosecond. After taking it out of its nursery pot, I tease out the roots, ripping some off (plants are tougher than you think) and put it in a larger basket with more soil that I've added a slow release fertilizer too.
Also, if you still have your heart set on moms, you can do what I sometimes do and put my hanging baskets on the ground.