Hi I am new to Armada having purchased it only a week ago.

I am keen to use the rules and mechanics to add in my own ships and universe campaign. Does anyone have any info on ship creation or would it be easier just to measure up other models and have them take on the stats of similar ships in Armada?

If you mean Is there a published or an unofficial formula for calculating point values for your own generated designs then the answer is no.

There is this site to generate your own cards

https://community.fantasyflightgames.com/topic/200905-kuat-drive-yards-armada-custom-carddial-maker/

Have a go, design your own units and any rules you need for special abilities, then ask everyone on these forums to evaluate your stuff and see if it is overpowered.