It's not a Captain Carrot run per-say, but he does have a big involvement in Multiversity, which was an 8 issue mini-series Morrison did throughout 2014-2015 I believe. It's definitely worth checking out, as is the case with anything Morrison touches...especially if it involves exploring DC's multiverse.
HAPPY! is an amazing television show. The comic is 4 issues long, and has way less meat on it then the series. It's still very good, but the show really elevated it to the next level.