Add a few more hits to the mix and singer-guitarist Chris Isaak is ready for Vegas. He’s got the flashy attire (bright red Western suit that was exchanged at concert’s end for a metallic silver one), the band (a bunch of old guys who can play just about any classic early rock tune) and the charisma (at one point, he walked into the crowd to serenade the people in the pit). Playing last night at House of Blues, Isaak demonstrated the degree to which he’s become a showman, something that was only amplified by the crowd-pleasing covers he chose to include.