> In increasing the block time to two minutes
When this was first raised I asked if there was a true motivation for it here: https://forum.getmonero.org/20/general-discussion/2401/increasing-the-block-time?page=&noscroll=1#post-4204
I still don't see a good motivation to changing a critical parameter like that, specially for something that makes usability less interesting. Anyways, I don't want to bring that discussion here in order to keep this on topic, but I'd appreciate some input there.
> It is not necessary to increase the minimum block size at all.
Then don't. Really, why changing an important parameter of a system in production, involving money, if there's no major opportunity of improvement from it?
Plus, letting this minimum limit low allows for the automatic adjustment system to start operating sooner. More opportunities to test whether it works well while the coins is still in its infancy. This minimum limit should be just a bit more than enough to comport any coinbase transaction, IMHO. (no, I'm not suggesting reducing it either! :))
Concerning the merchant systems: they should adapt to receive multiple payments, and having them confirming in different blocks. Monero works with stealth addresses, and soon there will be merge avoidance (important for privacy as outlined by MRL-0004). So multiple technical transactions to fulfill a single business transaction will be the norm. And they might have different confirmation heights even if the median block size is already much larger than that. So the merchants must take that into account. Better they start doing it from the beginning instead of having false expectations.