It's really up to you - my advice is not to get too attached to any single base location.

There's probably no reason to pick up your entire original base and move everything to the new location. What I've done recently is build a brand-new base and link it to my old one via portals.

Having a foothold in the center of the map is quite useful. Outside of that, I try to build up one reasonably well-stocked base in each biome.

A portal hub is important to have in order for this to be feasible, but that part can be located anywhere - I quite like using the empty biomes (mistlands/ashlands/deep north) as portal hubs, a lone tower standing out in the ashlands can be a pretty atmospheric place to transition between biomes/bases.