This weekend will be Willamette Rep’s last. Every seat will be filled, because this town harbors an almost bottomless affection for the underdog with all the accompanying guilt for not having done more. Maybe Artistic Director Kirk Boyd aimed too high. Maybe they didn’t choose the right plays, year after year. Maybe audiences couldn’t tell the difference between $30 seats at an equity production and the local amateur talent performing nearby at half the price. Or maybe it really was a failing of the Hult Center, where the venue has branded itself more powerfully than its resident companies. (Quick quiz: when you have had tickets to a show at the Hult Center and you told others of your plans, which came first in your conversation: the producing company or the venue/location? Probably the latter.) Fortunately, the Hult Center is something that can be fixed, especially the Soreng Theatre, which was an add-on to the Silva Concert Hall. Here’s what should be done. Demolish the current 700-seat configuration and put in its place a 350-seat “black box” theater (endlessly adaptable) with a dedicated outside entrance and a box office that fronts 7th Avenue. (It’s crazy that the interior of the soaring Hult Center must be heated and maintained, just so people can buy tickets.) Make this change and the next Willamette Rep might have a better chance. Call it a legacy if you like.