Currently network is fairly secure and incentivizes research well - there is no need to push PoR if security would be compromised, but research  for the solution might be continued.

ad) 1 and 4:

**Concerns.**

Currently ~6720 blocks are produced per week, what means **only** a maximum of ~6720 stakers can stake in average once a week (assuming equal stakes). Including pool members, already we have around ~6720 researchers.(*)

As we know there are no obvious limits in crypto sphere. Let's assume user base explodes (maybe a great BOINC discovery, maybe sudden CNN / BBC / etc coverage) and we have **one million** researchers. The only solutions to pay rewards daily is either pool membership or manual / automatic reward payments. Also, just the number of reward payments will **clog up** the blockchain. 

While researching and testing solutions, we should ask:
- Will the blockchain accommodate one million active accounts / researchers?
- Will the blockchain process ten million transactions per day?

(*) Although currently I believe around ~3000 are staking, as pool members are not staking individually. Nevertheless, we already scratch the limits here.