While Congress leaders provide their feedback and inputs, the final decision on the ministry's complexion will be decided by prime minister-designate Dr Singh, Congress President Sonia Gandhi, party General Secretary Rahul Gandhi and Sonia's political secretary Ahmed Patel.
A party source told this correspondent that "the family" will discuss likely names, with Patel providing the "inputs."
The Congress is planning to give the new ministry a younger look with several young MPs including Jyotiraditya Scindia, Jiten Prasad, Sachin Pilot, Sandeep Dixit, Deepinder Hooda and Milind Deora mentioned in this regard.
Rahul Gandhi is expected to make the final decision on the youth factor, according to highly placed Congress sources.
Should Rahul himself wants to join the Cabinet -- he has already indicated that he wants to stay on as Congress general secretary and strengthen the organisation -- some party leaders believe he could opt for the information and broadcasting portfolio that his grandmother Indira Gandhi held when she first entered the Union Cabinet in Lal Bahadur Shastri's government.
Interestingly, in a recent interview, his sister Priyanka Gandhi-Vadra mentioned that Rahul resembles Indira Gandhi in his manner more than his father Rajiv Gandhi.
Dravid Munnetra Kazagham chief and Tamil Nadu Chief Minister Muthuvel Karunanidhi arrives in New Delhi on Monday with an expected long list of demands. Karunanidhi is expected to ask for seven ministerial berths for his party, including key positions for his eldest son M K Azhagiri, the winning candidate from Madurai, his daughter Kanimozhi, a Rajya Sabha MP, and Chennai Central MP Dayanidhi Maran, his grandnephew and a former IT minister in Dr Singh's Cabinet till he fell out with his grand-uncle a couple of years ago.
While Palaniappan Chidambaram, the MP from Sivaganga in Tamil Nadu, may continue as the home minister, Dr Singh is short-listing candidates for the crucial finance minister's post.
However, reports coming in from Tamil Nadu say Chidambaram's re-election could be entangled in a long-drawn legal battle. Initially, it was reported that Chidambaram had lost the Sivaganga battle to his All India Anna Dravida Munnetra Kazagham opponent, but after a re-count, was declared the winner.
Although Pranab Mukherjee has held temporary charge of the finance ministry after Dr Singh underwent cardiac surgey on January 24, it is expected he will retain the external affairs portfolio, his primary brief.
Prime Minister Singh is keen to induct Montek Singh Ahluwalia, deputy chairman of the Planning Commission, as the finance minister, but Congress leaders feel the finance minister needs to be a career politician. Front-runners for this assignment are Kamal Nath, the commerce and industry minister, and Kapil Sibal, the science and technology minister.
With the Congress secure in the numbers game -- it only needs 10 MPs for a simple majority in the 15th Lok Sabha -- it is divided about accommodating past allies like Laloo Prasad Yadav, who has just four MPs including himself.
Laloo may find a place in the government only because Sonia Gandhi has a soft corner for him; he was the first frontline politician to defend her on the foreign origin issue. He will not almost certainly not get the railway portfolio, which Trinamool Congress leader Mamata Banerjee has reportedly claimed already.
The Trinamool has the largest number of MPs after the Congress in the UPA, with 19 Lok Sabha members.
While Nationalist Congress Party leader Sharad Pawar may get back his agriculture portfolio, the Congress is considering separating the fisheries department from the ministry.
It remains unclear if first-time MP Shashi Tharoor will be included in Dr Singh's ministry. While both the prime minister and Sonia Gandhi would like Dr Tharoor, who lost the election for the United Nations secretary general to Ban Ki-moon after the United States voted against him, included in the ministry, party strategists feel E Ahamed, the minister of state of external affairs and an Indian Union Muslim League leader, will have to be included. Trusted old hands from Kerala, from where Dr Tharoor was elected, like A K Antony and Vayalar Ravi are already in the top list for ministerial berths.
Dr Singh, Sonia and Rahul Gandhi want to get down quickly to the business of government. The prime minister has already met Vayalar Ravi, the parliamentary affairs minister, to discuss the first meeting of the 15th Lok Sabha. He telephoned Mamata Banerjee on Saturday to congratulate her on the Trinamool's huge victory and invited her to join his Cabinet.