Let's see ... Thyme Mint Lemon Balm / Verbena (actually, a whole ton of herbs would work well) Creeping Jenny / Lysimachia Honeysuckle / Lonicera (I use it in baskets, but it needs pruning every fall, and I usually plant mine in the ground or otherwise make a new basket after a couple years, it just gets too root bound) low-growing Sedums

Leave them for now, they are too young to pinch. The habit of ivy geranium is more vine like, it's not unusual to find some of the stems longer. If you want bushier plants later, pinch back the growing tips when your seedlings have gained a bit more size and have more than one leaf per each stem. Pinch, or cut, just above a leaf - clearly you don't want to do this when a stem has only one leaf. :) There is a latent growth bud located at the node (node = the point on the stem where each leaf is attached). Cutting of pinching off the growth just above that node will cause that stem to branch out. More branching will mean more flowers. Some longer stems on ivy geranium aren't necessarily a bad thing though...leaving some of the longer growth to spill over the side of a large container or drop down from a hanging basket may be desireable too, depends on how you plan to use them.

You could turn it so the back gets the sun for a while, or you cut slip a cutting back there. My ivy pellies root very easily. Or you could mix things up a bit & stick a taller plant in the back. OTOH I don't worry about the backs of my hanging pots. I used to turn them all the time to get even sun, and then I decided I didn't really care what the back looked like.

How did you divide it? You can't separate the roots--it just doesn't work. Taking cuttings from the growing tips does, and does not harm the plant. I have had the same hanging geraniums for about 10 years. Not the same plant but cuttings from them. In any case I don't think your problem was the cuttings, but the soil you had the plant in. Your geranium had leaf spot disease. Your cutting may be infected too so mix up a solution of 1 teaspoon of baking soda and 1 quart of water add a drop of hand soap--just 1 drop. Too much soap will burn the leaves, but you need it to make the soda stick. Baking soda is a fungicide. Put this in a spray bottle, shake and spray the rooted cutting every 4 days until you are sure it is not infected. Whenever you take cuttings from any peli it is important to have everything as clean as possible. Cleanliness goes a long way towards preventing blackleg, and the success of the cuttings and plant Good luck