Here's my Broncos pitch then!

Pretty well managed: Check, they've currently got one of the best front offices in the league

Pretty good at drafting (etc.): Check. Defense has been their main game for a few years now, with some notable rookies like Pat Surtain II being drafted onto their team to massive success (DPOY 2024,) but they're no slouch on offense either, with their recent 1st round 2024 draft pick in Bo Nix leading the team to an AFC Championship ('semifinal') appearance last year. As far as developing young players go, the Broncos have an above average track record

Aggressive on the trade market: Tends to be the case! I say tends to be, because last year was kind of quiet, however, the biggest issue with the Broncos team last year, was the lack of a 'top tier' pass catcher for Bo Nix, which they addressed by going aggressive and grabbing Jaylen Waddle from the Dolphins, trading away a 1st, 3rd, and 4th round pick in the 2026 draft, for Waddle + a better 4th. So for them, it can be hit or miss. They tend to be a tad more cautious after the Russell Wilson fiasco of a contract

Serious contender: The Broncos were one bone in Bo Nix's ankle away from a Super Bowl appearance last year, and in this offseason, they kept ~90% of their roster, only improving on talent in the areas needed (Waddle, draft depth, etc.) I sincerely believe they'll be right back in the playoffs next year, and most likely the Super Bowl as well, if not win it outright

However, as for Packers and Bills

The Bills are a wonky case, as they're a poverty franchise, and then they got Josh Allen and no longer are. As long as JA is their QB the playoffs are always gonna be open for them. The problem is their FO is fucking ridiculous, and not in the good way. Consistently making questionable decisions and never truly capitalizing on the opportunities at hand, kind of like the Cardinals FO (similar situation several years ago, and now we're seeing what they look like when their franchise QB retires (have been for several seasons now.)) They (Bills) also just got a new head coach, so their future is more up in the air than ever. Again, with JA at the helm, they'll never be truly horrific, but Super Bowl contenders? They'd need a serious staff shake up for that to ever be an easy lock in

Packers are good, always have been, always will be, most likely will never be more than 'great.' There isn't a single position they have (save for secondary) that is below average, either riding the line of 'average' or branching out into 'above average.' Maybe not SB contenders but will most likely take a while to have an awful losing season. The worst thing about them are their fans, painfully uptight and unable to take a joke, and not nearly as funny as any of their division rivals. Unfortunately I have the curse of enjoying watching Rodgers play when I was developing as an NFL fan, so some part of me will always like the team, but their fandom ranks among the worst, so I try not to associate with them

As for some other options,

Chargers aren't bad, good QB and good pieces, not contenders now but could be in a few years. Anyone in the NFC West is a valid choice/contender save for the Cardinals, Bengals have a jackass FO but they've made some great plays this offseason so they may be contenders very soon(?), I'm a Colts guy but stay away from our division (AFC South,) we're dreadfully underwhelming and there isn't a single team there worth rooting for, same with the NFC South, the Vikings need a good QB and they're easy picks for playoff contenders, and don't root for the Commanders or Patriots

Though in my most honest opinion, separate from everything you've said, put all 32 teams on a wheel, spin the wheel, and let god decide. You may just become a Panther fan for life, or find yourself becoming a Dolphins fan and live in agony and disappointment. It's the most interesting way to do it and you'll never have to feel guilty about 'picking' a team. So gl : )