The Loogey is about 22.5" wide compared to the Broadcast's 20.5" width. This increase surface area significantly which does contribute to down-the-line speed. Also, as I mentioned before, the Loogey has fins with a bit of cant and toe-in and the standard fin is 3.5" deep. All of that will combine to add more drive than what you are currently accustomed to. The width of the Loogey does tend to make it feel less responsive rail-to-rail than some other boards, but it is by no means a slouch. IMO, it will feel more responsive than your Broadcast.
I haven't ridden the quad fin option on the Loogey, as yet. It looks like it is only a few dollars more and so that might be a worthwhile option just for the extra flexibility you'd gain with two extra fin boxes, plus typically quads have more down-the-line speed than twins.
IMO, you'd be pleased with the performance of the Loogey in comparison to the 4'9" Braodcast and at your weight and skill level will ride fine behind the boat you describe.
As Hate N Pain points out there may be other options available that are better suited to you.
Same 'ole, same 'ole disclaimer: I organize events and solicit donations from everyone with a hearbeat.