DS9 brought in a TNG character - Worf - to spice things up. Although the impact of that can be debated as being a detriment or improvement to the show, the principle of "The Worf Effect" exists nonetheless. By means of Q, Will Riker appeared on Voyager. If you could've put any TNG character onto Voyager as a regular crewmember, who would it be and why? For the sake of logistics, let's just assume they've been transplanted by Q (nice and easy). For me, maybe Beverly. If something had happened to the EMH, her character might have been more interesting in the Delta than she was in TNG, using her experience and expertise in a way that wasn't always so intertwined/overshadowed by Jean-Luc. Your choice?