Your response is something I totally sympathize with to a degree. Harrison Ford being Indy is a timeless and seemingly irreplaceable role. But I think unlike Dirty Harry or even a highly successful, influential, and active series such as Alien and the implied role of Sigourney Weaver's Ellen Ripley, I see Indiana Jones as an action-adventure movie hero that has many great adventures to go on just as James Bond does with missions. It's hard thinking about that and having to swallow: "just three movies?" or five movies, if you wish to include the latter two. I know this invites a potential Pandora's Box, where "milking" the series could be a possibility; trust me, I'm very weary about that. But I think it'd be cool to see a new face take on Indy and though it would be very hard if not impossible to fill in Harrison Ford's shoes, that does not mean that a reboot would not be good or memorable.