That's the dynamic that eludes me as well. Forget the whole "Survival" aspect a bit.With some thought put into it imagine perhaps a different type of moba like this:

Remember the good old strategy days? Well, back then you had to provide things for your base etc as a whole - such as farming minerals etc.

5 a side starting on either ends of the "map". Each with a "throne"-type thing and/or base to defend. Basic moba stuff you know. However, you would then need to collect say wood,stone etc to build certain things. This can include weapons and structures. Each side will then go about building their base (Which they can do however they want in order to protect their "throne" or w/e) which allows for extreme tactics. Such as for example - when go against an enemy hero that say has the ability to break down walls with a huge charge - They can go about setting traps for that hero etc.

So you'll have a team of 5 with heroes that will do different things - gather, build etc and still need a system for "farm" and leveling which I have not thought of..

So basically, imagine a moba where you can build your own base and customize your weapons, build traps and other structures etc etc.

Just spit-balling here so if you concur no worries please do discuss.