personally I think it'd be easier to jump back in? - you don't need to level/exalt all that fodder and if you really wanted to start fresh you could sell/giveaway whatever you had left, that way you still have a little treasure/gems to work with to redo your lair

that's just my 2c though! if you end up feeling overwhelmed with selling i'd be willing to find dragon sales of similarly aged/gened gen1s for you/deal with the new gen1 spreadsheet/site!