You left off the Patriots from your list of teams the Broncos played this year...perhaps you would like to forget that game. You also left off Baltimore.
Let's not forget that BOTH AFC Wildcard teams came out of the Broncos' division this year too, so that's another 4 games against playoff teams...7 in total.
The Broncos have the second most difficult strength of schedule next year, though...based on what happened this year, anyway.
No, I didn't - notice I said "via divisional match-ups." Each year, the teams play their own division twice (6 games), one division from the AFC, one from the NFC (8 games), and the remaining two teams in their conference that finished in the same place, by division.
So the Donkeys played New England and Baltimore (who won their respective divisions in 2012, as did Denver). This coming year, they'll play Cincinnati and Indy in addition to the teams I listed.
I only compared the 8 games from the division match-ups. Last year, the AFC West got a huge break in that, as evidenced by the Chiefs record, and San Diego also just missing the playoffs. Powderpuff schedule. Not only did the NFC East utterly suck, but it sucked worse in the beginning of the year (until the Eagles, Giants, and the Cowboys somewhat straightened out...and if you go back and look, you'll see that Denver (and KC) had finished up with the NFC East by week 8).
I'll take the bet that the NFC West next year will be a bit better than the NFC East was this year...and also that the AFC East this year is a wee bit better than the AFC South was last year. The only semi-quality team in the two divisions the Donkeys got last year was Indy (the Eagles were 1-2 and utterly horrible when they went to Denver in week 4).
It's not just who you play, but when you play 'em, and Denver lucked out in both last year.