I wish someone had defined a bracket between 2 and 3 - I can't make a decent bracket 2 deck.
Much as there is a massive gap between 3 and 4, I think the most significant gap exists between 2 and 3.
"No intentional two-card infinite combos or mass land denial. Extra-turn cards should only appear in low quantities and are not intended to be chained in succession or looped. Tutors should be sparse."
This is too vague - I'd make this more explicit and instead say
"No infinite combos, land destruction, extra turn or tutors which cost 2 mana or less (a card is a tutor if it causes you to search your library for any card excluding lands)"
Then simply remove that restriction for bracket 2.5, and simply have 2.5 be the space where people play without game changers.
At the moment Bracket 2 is impossible to brew in. How many tutors is 'few' tutors? I really like the idea of building mono blue Baral Storm within Bracket 2 - here is my list https://moxfield.com/decks/k_lAyk96nU-0NTjeHlW0Ig
However I cannot imagine sitting down with someone who doesn't have issue with the deck built in bracket 2. God I'm still not even clear what counts as a two card combo. The only two card combo I can think of is thoracle, although I guess there are those 2 enchantments (sanguine bond and exquisite blood or whatever) that go infinite, but even that combo requires another card to cause life loss to set things off. I'm sure some people would consider drake and deadeye a two card combo though.
Anyhow why can't WOTC give me a space to build an optimised deck without game changers in. This would help keep people who want to brew like me away from more scrubby players. Anyhow that's my thoughts. Peace.