and if the total miners stay the same that means hashing rate and difficulty stay about the same
hence mining cost will be essentially double up... to mine 12.5 BTC needs 2 blocks of 6.25 BTC
and based on stats history, hash rate and difficulty actually always keeps rising in time
this might be the reason why the price reached ATH ~12 months after halving
Agree. Some lower scale miners may quit mining if they can't afford to run their equipment and pay for energy costs. This would decrease difficulty for a short while, until it levels out again and then rises. I guess this is the reason it can take circa 12 - 18 months.
i actually because that these small miners whom you call "lower scale" are the ones that aren't going to quit that easily. simply because if you have 1 ASIC for example and are mining bitcoin with it, you don't have that much of a high electricity cost as the big miners do. so even if your earning reduces you may not care as much, specially since this type of miners are sometimes hobby miners and believers in bitcoin's long run future. so they may not even be selling the coins they mine!