The former leader of the Tories in Scotland claimed her experience of campaigning proved voters responded to parties which offered a list of candidates from different backgrounds and areas of interest.
Ms Davidson, a long-term critic of Mr Johnson and his Brexit strategy, said it was a "big risk" to remove the Tory whip from MPs such as Rory Stewart, who were well-known and respected in their communities.
The group of MPs, including such veterans as former chancellor Ken Clarke, had the party whip removed after taking part in a rebellion over no-deal Brexit which saw the Commons take control of the parliamentary agenda last week.
“The Prime Minister’s reason for sacking 21 MPs last Tuesday was because they voted against the Government to try to stop a no-deal Brexit. Government spinners were quick to claim it was nothing personal, just enforcing discipline," Ms Davidson wrote in a column for the Evening Standard.
But these weren’t MPs who lacked discipline. They weren’t serial rebels; in fact, this vote was the first time some of them had broken the whip in their entire careers."
Davidson, who resigned as Scottish Conservative leader last month after eight years in charge, added: "I might serve in a different parliament in a different part of the country to the House of Commons but one thing I do know is campaigning.
"When I was head of the Scottish Conservatives I led our party through seven national elections and two referendums in just under eight years, and increased our support at every level.
"I believe that showing voters that you are a broad church, with lots of different types of people from different backgrounds and areas of interest, helps a party increase its appeal.
"Just as voters in rural Cumbria have different priorities in their daily lives to those in commuter London, so we as a party need to show a diverse slate of talented candidates who can deliver on those priorities in Parliament.
"Binning Rory Stewart in Penrith and Justine Greening in Putney, who have been re-elected multiple times by those communities and whose talents have led them all the way to the Cabinet table, seems to me a big risk."