It seems that a BBC telly season is about 6 episodes. If true, that would mean that the actors would most likely work on other projects in the off season, as their salaries may not have been very high.
Bannister probably had other projects (long-running play, perhaps) that precluded his appearing in the rest of the series. But with Lucas gone, I think the show began treading water as far as replacement "juniors" went - no one played with his style.
English MA: Symbolism/my life. "Truth vs the world" - Boudicca of the Iceni

I don't think it would have made sense for Lucas to be in it anyway. He had already left the staff of Grace Brothers, so would not have been there when the store closed.

I saw an interview in America with Bannister and he said that they just had no idea of what to do with his charicter to help his charicter developmen(there a catch phrase of read into what you like) and that he had other things on the go and was not put out by not joining with the gang. Iman had a different version of things that Bannisters kept putting ideas out(either him or his agent or someonewhere his charicter would come out on top)
I saw a few eppys and it did nothing for me

I would've liked that better! Seeing how nearly treated him like crap in Grace Bros. and then one upped them with him being millionaire would've been hiliarious than this one.

I don't think he would have had to been a playboy. He could have been a married millionaire with kids, who buys the house and runs it to everyones chagrin. This would have worked beautifully if he could have pushed Miss Lovelock and Mr. Rumbold off their high horses and made them relate to the others better. I think I may write David Croft and ask permission to write a fan-fic!

I don't know If I saw Mr Lucas as the type to retire out to the country anyway.
It worked well with the core 5 and additions they had.
My invisible wife says it's okay to see digital people:)

I think so as well and it would've been interesting if there was a thing between Mavis, Humphries, and he. Unfortunately I read in the official Making of book that Trevor thought he was too old to play the playboy type and thought he would look like a perv if he chased down younger women at his age so he declined, which was a shame, indeed.