This is from Wikipedia on Convy's early career:

Convy started his career in the entertainment business as a featured performer and singer in the Billy Barnes Revues of the 1950s and 1960s. He appeared in the 1961 Warner Brothers drama Susan Slade, playing Troy Donahue's rival for the affections of Connie Stevens. Convy went on to became a Broadway actor, starring in Fiddler on the Roof (1964), The Impossible Years (1965), and Cabaret (1966). He also appeared in the Roger Corman film A Bucket of Blood, playing Lou Raby; and the soap opera Love of Life, playing Glenn Hamilton, a rapist.

Had Roger been killed off as originally planned, I doubt LE would have returned as a new character, and if so it may have been similar to Thayer David's return via a flashback to another time period.  It was too close to bring him back again, especially at this point in the show when a character was written out, the actor was gone.  Bill Malloy was to originally never been killed off, so he may have taken the place of Roger.

[spoiler]As was stated a while ago, it's amazing that Dennis Patrick played two characters so different.  Not only does Paul Stoddard look decades older, he is also a passive/weak character who takes a lot of abuse.  I can see how Jason manipulated Paul as well as Liz, as they both are his victims. 

On another tangent, It probably can be theorized they do not really look alike as it never is stated so, which is something the present time tended to do more then the post 1795 flashbacks.[/spoiler]

[spoiler]When Roger goes looking for the paintings that he "bought" from Sam, they should have had him find Barnabas' portrait.  Though the character may not have been cast yet.[/spoiler]

I liked that they used real footage of a car on fire too.

There were some new photo's but most were in several other books.   
What surprised me about the 2004 pilot was who was actually behind the project being shelved.  I thought it was the reverse.

This is sort of like the end of a later episode when Jason is walking through the woods, hears dogs howling and gets a real frightened look on his face as something approaches. 

This is never referred to ever again and when Jason next appears it is like it never happened.

They also had Barnabas in the sunlight way too quickly (ep. 2 or 3) that we didn't get his problem at being  a vampire long enough for his cure to pay off, it didn't mean anything.  The OS waited a full year to do this, and it happened after his origin was told.

They should have had the seance as the final scene for season one with Victoria appearing in 1790 as the cliffhanger.