Now that you know how to create pickups and jump pads, you should be able to figure out any other gameplay object type. I'll give a rough overview of some of the common ones here, without going into full detail. This section is meant to be more of a reference guide, but if you want to add some of these object types to your level now, it'll be a good practice.
Let us begin with the teleporter.
A teleporter is something that transfers matter from one point to another, more or less instantaneously.
To place a teleporter pad, select Navigation | Teleporter | UTTeleporter and place one in your level. You'll also need an exit point for your teleporter. You can create another UTTeleporter, which will spawn with a base in the level.
Under the Teleporter properties, there's a field called URL. This is the Tag of the teleporter destination. Select the teleport destination, bring up its properties, and open up object. In the Tag field, give it a name like...