Landscape mesh(es) made in C4D - single or multiple meshes okay?

Quickie history - I'm an illustrator, I use C4D 9.6, I joined a group of guys who are making a game. At FIRST it was going to be 2D only, then they got a new programmer who uses Unity - so here I am!

I'm now being tasked with taking my giant 2D illustration of the entire 1st level (which was 3 - 2048 panels when finished - see attached image) and making it in 3D.

Sooooooo...

Should this:

1 - All be 1 gigantic mesh of ground/sand and mountains, with separate meshes for rocks and ship debris

Or

2 - Can I make a handful of land masses with separate mountains - exporting them all as a single FBX model (which would make it easier for texturing, which I know if just laziness on MY part)?

3 - Or would it be better to learn Unity's landscape creation tools and build the general landscape and mountains in Unity, and have separate FBX meshes for the rocks and ship debris?

Any help would be greatly appreciated!

-Lew

 

Let me summon @hippocoder *chanting summoning spell

 

Just realized this was moved - sorry to anyone out there for posting it in the wrong place.