Some of the wishes on Star Mountain are this. Special note goes to Luigi's wish. I wanna be a great plumber like my brother Mario.
The music playing in the background takes this Up to Eleven.
Bowser's Pet the Dog moments in Monstro Town where he meets deserters from his army and wishes them well in their new lives after they apologize for fleeing. Who knew Bowser was a Benevolent Boss?
And let us not forget the rather heartwarming and awesome moment where you find a (female!) chain chomp imprisoned in Booster's tower. Bowser not only manages to calm her down and befriend her just by staring at her and offering her a few gentle words (even asking Mario to look away from her while they're talking as she's apparently very shy) but convinces her to come along as Bowser's first new weapon. Who knew Bowser was a Chomp Whisperer?
Many fans find this scene so heartwarming they refuse to sell the Chomp to a merchant even after Bowser gets better weapons; they just keep her in their inventory.
In the epilogue, we see him actually rebuilding his Castle alongside his minions, rather than overseeing the process.