One big map or many small maps

Hi,

I'm trying Oruxmaps and Mobac for the first time. Not done much experimentation yet. I'm determined to generate offline maps, partly because I want to customize their content, partly because there's not much cellphone reception where I hike, and partly because I don't like paying for a mobile data plan.

Just wondered whether more experienced users have any advice on the right "size" for individual offline maps? I'm generating my own maps using MOBAC, in the sqlite format (unless someone advises me otherwise). Should I just combine all the tiles from all the layers of all the areas I'm interested in into one giant sqlite database? For example I may include rectangular regions in zoomlevels all the way up to 15 for my favorite hiking areas, much larger regions in lower zoomlevels, all the way down to whole-world in very low zoom levels.

Or, would I be better off subdividing it by area or by layer into many smaller maps?

What, if anything, is the advantage of a single big map over many small ones, or vice verca?

In case my question was too vague, I'll illustrate with an example....

Let's say I'm interested in three different areas, with some layer overlap:

1. The Newfoundland East Caost trail in zoomlevels up to 15 (perhaps 150,000 tiles).
2. Rocky Mountain National park in zoomlevels up to 15 (perhaps 30,000 tiles).
3. The whole world in zoomlevels up to 8 (perhaps 85,000 tiles).

I could:

(a) Shove all 265,000 tiles into a single sqlite map.
(b) Use three separate sqlite maps. To avoid tile duplication, I could include only layers 9 and above in the first two.
(c) Ditto, but actually duplicate tiles in layers 8 and below, where the regions overlap.
(d) Some other organization? Any suggestions.

If I go with option (b), will Oruxmaps know to automatically transition between maps as a zoom below level 8 and above level 9? Or, is this switchover a manual process? Or is the more wasteful option (c) better?

Thanks for any help you can offer.