I don't think changing the gameplay experience, be it the callouts or images, is an option. If memory serves, a big part of Farsight's agreement for the B/W licenses means not altering the tables from their factory releases. This is what they've said in response to requests to add mods as trivial as, say, gumballs in TZ.

Regardless: Covering up the likeness on the BG/playfield would be distracting, sure, but replacing RJ's voice in the callouts would be just horrid.

Also, just to play devil's advocate: Pinball Arcade's renditions of tables tend to be way, way easier than the real thing (or VP renditions, for that matter.) TAF ain't exactly a hard game. Can't help but think the Pinball Arcade version would be so easy as to almost be boring. Don't get me wrong: TPA can't be considered a true digital pinball museum without it, but I have a sneaking suspicion that anyone familiar with TAF would get tired of it pretty quickly.