The third round tie is the first of at least eight matches in 30 days for Smith’s team, with the figure rising to nine should they progress past the Reds.
Villa have not won an FA Cup tie since 2016 and Smith is respectful of the competition’s importance to supporters and the high-profile nature of a tie against the Premier League champions.
But with the fixture list increasingly congested, the need to give stars including Jack Grealish, Douglas Luiz and Ollie Watkins a break will take priority.
Conor Hourihane, Tom Heaton, Marvelous Nakamba and Kortney Hause are among those likely to come into the team.
Smith said: “As much as I love the FA Cup, I did feel with the congested fixture list it might be postponed this year to free up spaces in the calendar.
“We will have to make some changes and I am certain Liverpool will as well because there is a hell of a programme in January.”
After taking on the Reds, high-flying Villa host Tottenham and Everton before travelling to Manchester City on January 20.
Smith will assess Ross Barkley before deciding whether to hand the on loan Chelsea star an outing in the cup.
Barkley has missed the last seven Premier League matches with a hamstring injury and Smith will continue to exercise caution, with the visit of Spurs a more likely date for his return.
He said: “Ross wasn’t close to making the match against Manchester United last Friday.
“He just needs a few more minutes on the training ground. I am not sure whether I will start him in the cup, he needs a few more minutes.
“I fully expect him to be ready for our next Premier League game.”