I am quite new to mapmaking etc and i really wonder cause nearly ALL of maps made here have very low amount of minerals at main, nat and expo
usually there are 8-9 at main (or +1 with 500 or 200) and nat has got 7-8
the maps here often have like 7-8 at main 6-7 at nat and 6-6,5 at other expos oO
Usually the mains have 8 minerals, the nats 7 and the minonlies 6.
Mains with 9 minerals once were an experiment, it was supposed to help p a little against z. But it also favored massing in general. I don't think many of those who put 9 minerals in in the mains really know why they do this.
A 500-min block in mains certainly is unusual...
So, I don't think 9 minerals in mains actually help the balance of a map much. But the gameplay certainly is changed towards massing.
The mappers on this page don't seem to like the massing trend nowadays a lot, so unless it is really necessary, many of them don't add that ninth mineral block.
500 or any edited mineral in the mains is to boost macro. So the eco boost only lasts until your finished with it - then after it is finished, you loose the eco boost just in time before you have 28 scvs or probes (not drones) so the regular 8 minerals are balanced with the amount of workers u have. So its about watching your workers (the amount) and still having that eco boost. So if you have 2 edited minerals, then you may have to cut the amount of scvs earlier in order to have a good pace of production.
the number of minerals in main/nat/2nd nat is a question of balance. the less blocks, the more is the advantage shifting towards z>p>t. in zvp and zvt, p/t cant use their strength of pumping workers to their full extent, while zerg can get optimal mining speed with their normal drone count. in PvT, restricting minerals limits the number of turrets and mines (->vults) everywhere, which helps protoss a lot.
less minerals around main and nat also help the static races, because they cant expand as fast as the more mobil race of the matchup. in return, you can use increased mineralcounts to help the static races, as i did in dreamcatcher. 2nd expo was so hard there, that i even applied 10 blocks into the main (after testing with 8 and 9).
modified values of the blocks shift the gameplay heavily. in my Disruptive Factor, almost all blocks are modified, so the longer you mine at one spot, the less productive it gets. this forces you to expand earlier and more aggressively than on standard maps. DisFac is quite turtle-friendly from its layout, but due to the mineral values, you cant stay in your base, but need to expand out into the combat zones. that really changes playing style and makes very cool and dynamic games.