Quote from: OliverChassa on January 18, 2018, 10:02:38 AM

As I have been reading, Ethereums success and expansion is leading to new challenges: growing need for storage space, thus growing costs and at the same time issues like fewer who want to run full nodes and risk that the network could be run by few (and more centralised?).
https://www.coindesk.com/blockchain-bloat-ethereum-clients-tackling-storage-issues/

Developments are ongoing (protocol changes towards sharding), but not quickly enough to deal with all these challenges.
https://www.coindesk.com/modest-proposal-vitalik-unveils-multi-year-vision-ethereum/

But besides technical developments, since energy is a significant cost, what about countries where energy costs are pretty low and not growing sharply (okay, at the same time you need to have a stable and permanent connexion, both for electricity and internet) as well as safe/secure?

Anyway, as often in our society, energy is the key...:-)

Your statement of changes not being quick enough is very subjective. The transition to PoS and Casper are planned, but there is already a solution called Raiden Network. You may want to take a look, as it is fully operational and allows micropayments.