is a Timer Remote Controller usefull to have

I want to do some night photography and have a little cheap wireless remote. Should I invest in a shutter remote controller with the wire. and if so, can you give me an idea of what to get. I have a Canon 7D.

Use Magic Lantern if you want to use sound remote triggering form your camera. It is nice to use when you forget you wireless trigger. Magic Lantern also adds an intervalometer function and it is free.
Cable trigger is useful if you are standing besides your camera, otherwise use the wireless remote.

The best part about a wired remote is that they don't use batteries in their basic mode (push the button to take a picture OR, lock the button to keep taking pictures) so they always work.

I have one of each, and intervalometer remote that I rarely use, and a simple lockable button that I use most of the time. I only have the inexpensive third-party remotes and they work fine. I paid $9 for my basic button remote from Amazon.

You can get one with a built-in timer, or you can do what I used to do until Canon put a Bulb timer in the 7DII....get one of the cheap, $3 cable remotes with a locking switch, lock it open and set a timer on your phone.