The project has been in stealth up until recently so some of the details still have not been posted but here I will try to answer your questions to the best of my ability.

1.Technically it’s not necessary to obtain a Gridnode to mine PKT, but in order to take advantage of the upcoming services (VPN, Bandwidth Marketplace, WiFi sharing on-demand web hosting, and more) you will need a trusted device (Gridnode), so it makes sense to get one, especially if you don’t have time to keep up with it.
2.Currently the team is lead by Caleb Delisle the creator of the worlds first decentralized mesh network (CJDNS): https://wiki.archlinux.org/index.php/Cjdns, along with a team of global engineers. The GIT for the project can get found here: https://github.com/pkt-cash
3. Max supply is set to 6 billion PKT.
4. Block reward is currently at 2699 & block time is 1 minute.
5. There is an alpha explorer available here: https://alpha-pkt-explorer.cjdns.fr/#/PKT/pkt/home
6. A preview of the roadmap can be seen here in one of Caleb’s recent posts: https://www.gridfinity.com/packetcrypt-mining-bandwidth-into-the-future-caleb-james-delisle/

Happy to answer any more questions you may have for me. Fair warning I am independent from the team, and operate as an Gridnode enthusiast and early adopter of PKT.