If Harley Davidson was to ask me what they needed in their product line, it would be something a little smaller, lighter and less expensive than the Sportster. My current ride is a Yamaha Virago (now V-Star) 250. It's 324 pounds, 250 cc air-cooled V-twin, 21 hp, 86.2 inches long.
The Sportster is 489 pounds, 883 cc air-cooled V-twin, 52 hp, 89 inches long.
The Buell Blast
was 360 pounds, 492 cc air-cooled thumper, 34 hp, 78 inches long. (Was. Now, it's a cube.) When I was thinking about my first bike, I considered the Blast, and some recommended it to me as a good starter bike.
Now, Harley doesn't have a bike in their line that fills that gap at the lower end of the range. I guess they must feel they don't need it.
So, what I'd like from Harley would be a 400 (or thereabouts) pound, 500 cc, 35 to 40 hp or so air-cooled V-twin about the length of my Virago or the Sportster. Standard or mild cruiser style. Fuel injected would be nice, as would belt drive; something that splits the difference between my Virago and the Sportster. But there are those (both in and outside the H-D community) who deride the Sportster as not being big enough and powerful enough to be a Real Bike, so I'm guessing the chances of Harley coming out with that bike, either as a Harley or a Buell, are slim to none. (If they're deliberately courting exclusivity as their market niche, they probably don't want to dilute their branding with such a bike anyway.)