A reward is defined as a one-time unlock, you can't lose a reward. This is important!
You are limited to 20 nodes total when starting out.
Master will allow you unlimited, since GM is quite exclusive to reach. Maybe even Master is too hard to reach and unlimited should happen at Diamond? I don't think this is the best way to learn the game, but getting into Master with just 50 nodes might be hard. Increasing the Diamond unlock to 100 would be pretty useless however, as that's not a very meaningful downgrade from just rewarding unlimited.
- Gold: 30 nodes
- Platinum: 40 nodes
- Diamond: 50 nodes
- Master: unlimited nodes
These changes would incentivize unranked, because for people ranked lower than Master, if they want to have fun with a giant AI, unranked would be the only place to run it. I think this would be a good thing, as it creates a more outlined use for unranked for beginners. They might have a big AI they made for campaign and unranked allows them to play it.
Counters/Tags might need to be gated behind some sort of unlock, so they don't open up straight away. I'm not sure where the best place is. GFX suggested making them an XP reward. This XP reward shouldn't be too harsh, but enough to make people enjoy the game for a while without them, so they see the game is already very complex and deep without a need for variables.
The Big Reset:
If these are implemented, there would probably need to be a one-time Big Reset (ghosts stay, but everyone is demoted to a rank of 1000). To stop this from being very annoying, a good way would probably to turn it into a fun community event. There will be a wild scramble for everyone to try and rank up to their previous ranking using smaller AIs. Most GMs will probably not suffer, but lower ranked Masters and higher ranked Diamond players might find the biggest hurdle to unlock Master to get access to their old AI again (you could still run it in unranked though).