I've just attended my first Comic Con (London 2018) and loved it. Learned a lot about preparedness and next time I'll bring a foldable seat - my feet were killing me 2 days after the event, and I walk 10-15 miles a day in my job so I'm used to walking!
Since my list of people who I've met is quite short I'd like to add my suggestions:
John Barrowman (Dr. Who, Torchwood, Arrowverse)
Bruce Boxleitner (Babylon 5, Tron, Scarecrow & Mrs. King)
Mira Furlan (Babylon 5, Lost)
Peter Jurasik (Babylon 5, Tron)
Bill Mumy (Babylon 5, Lost in Space)
Andrea Thompson (Babylon 5, JAG, NYPD Blue)
Walter Koenig (Babylon 5, Star Trek)
Barbara Bain (Mission Impossible, Space 1999)
Katey Sagal (Married With Children, Futurama, Sons of Anarchy)
Richard Dean Anderson (MacGyver, Stargate SG1)
Christopher Judge (Stargate SG1)
Amanda Tapping (Stargate, Sanctuary, Supernatural)
Kevin Sorbo (Hercules, Andromeda)
Lucy Lawless (Xena, Spartacus)
Bruce Campbell (Hercules, Xena, Evil Dead)
Mads Mikkelsen (Hannibal, Rogue One)
Karl Urban (Star Trek, Judge Dredd, Lord of the Rings)
Westworld TV series
Who know, I might see some of them :)