It's interesting... some of the replies. If you were asking about an AR-15, you would find very few people who would vote for a 20" or longer barrel (for a standard .223/5.56mm rifle.) The 16" barrel has taken hold of that market, and now a 20" rifle, and particularly one with a fixed stock, is looked at like some relic dug up. "OMG! Would you look at that... it has iron sights! Not only is the rifle an antique, but I'll be the shooter was, too...
"
In a pistol cartridge lever-gun, as I stated before, I don't really think you gain much from an extra 4" barrel... unless you are trying to extract maximum performance from standard cartridges. Weight and balance is something different to everyone, mostly because everyone is built different, and handles their weapons differently as well. My 20" Marlin 1894 isn't my ideal lever-gun, but it works well enough, and checks all the boxes except one, so it's not going anywhere.
In rifle cartridge lever-guns, I would say the opposite, generally. I have a 20" Browning 71 in .348WCF... I wish it had the 24" rifle barrel some days. Not that the 20"er doesn't get the job done, it most certainly does, but the rifle barrel would make it a little easier to get it there. Am I trying to dump my 20" 71 for a 24" rifle? Not on your life.