There are some good bits to a bard, but I think I'd do first level Rogue, then one level of bard, and then all rogue with emphasis on the knowledge skills for history, etc. and/or give a couple levels of expert (even though I don't think that is as good as straight rogue). (At this point I am afraid of the min/max problem creeping in by factoring in expert levels. But let's face it, Indy really is min/maxed in a couple spots.)
I'd allow none of the bard magic stuff and compensate with a little better Fort save. After all, Indy is resilient as all git out.
I see Indy as basically a rogue who had a "skill/talent" for archaeology (due to his dad) and a first rate education. I'd give at least 2 bonus languages (no matter his INT score). I don't think he is as persuasive as a straight bard would be, though he is quite charismatic.
I've wanted to play an Indy type character or the Brendan Fraser character from Mummy in a near-modern game for some time. Sadly, I'm the primary DM and I just love my late-middle ages Sherwood Forest Campaign too much to switch. Maybe I can talk one of my players into DMing us in a Mummy type game.
Good luck Ero Gaki! I envy you. Play it like you mean it!