So, I have been making a steel type team (without mimicking Steven and other canon characters) and I have been thinking wrongly on how to utilize steel types potential. I know what 3 pokemon I want to use, but not sure about the other 3.

Current Team: Metagross, Aggron, Magnezone, Scizor

so, can anyone help me?

Magnezone and Scizor are Steel types you should defiantly use.

And if you want coverage over ground types for later in the game use Ferrothorn.

So this is a mono steel team?

yup. I am striking bisharp and lucario from the team. But I am adding aggron, magnezone, and scizor.

Okay you might wanna edit that in the thread. So far you have Aggron, Magnezone, Scizor, and Metagross. You want to have steel pokemon that maybe have levitate and fire resisting abilities. That way, if you have a mono battle against one of those types, you will have back up. Moves that kill those types too are also good.

I was thinking Empoleon, but the stats are kind low. then again, there is heatran. but I would have to catch that and check the nature to see if it is one I need.

Empoleons are exceptional. Heatran is even better. Attatched with an air balloon, the thing wont have a problem with ground or fire! Well, that is if you attatch a Flash Fire ability (Preffered ability).

You can try Brongzong or Steelix