The enitre concept of 'bipartisanship' is foreign to us in the UK. Over here, the Government proposes, the Opposition opposes and both sides use the party Whip to ensure that MPs vote as they are supposed to. Free votes are only allowed on matters of conscience, rather than policy (eg the death penalty).
By observation, I find that the three great weaknesses of your system are: the separation of Executive from Legislature; the addiction to a bipartisan approach; the lack of any other party representation in the Legislature.
In the first instance, if you had a First Minister/First Secretary/Prime Minister who was the majority leader in the House, and who had to choose their Cabinet from elected Representatives, the entire Executive would be visible to scrutiny by, and accountable to, the House. As it is the Executive is isolated in the White House and the Cabinet is formed of people nobody voted for -and can get away, sometimes literally. with murder.
The seeking of, and apparent need for, bipartisan support for Government legislation speaks volumes about the lack of party discipline in the US. If a party with a clear, if slim, majority still has to seek voted from the Opposition, then clearly that party is not properly whipped. Either that or contains too broad a spectrum of views.
Which brings me to my third point. A two-party system makes clear policy-making next to impossible. The Repubicn Party runs from Fascism on the right to Coproratism on the left. The Democrats run from Corporatists on the right to Austerity Conservatives on the left. That basically prevents consensus within parties and limits the abilty to make or carry out cohesive or even coherent policy. It also means that no other voices are heard. The centre and left of the American people have no voice.
After the 2019 election, the Hous of Commons looked like this:
Liberal Democrat 11
Scottish National Party 48
Democratic Unionist Party 8
Sinn Fein 7
Plaid Cymru 4
Social Democratic and Liberal Party of Nothern Ireland 2
Green Party 1
Northern Ireland Alliance Party 1
Now Sinn Fein members do not take their seats, as they are Irish Republicans and will not take the Oath of Allegiance. Even if they did, however, the Government would never need their votes to ensure passage of a Bill, as things currently stand. In the past, Governments have had to rely on voting pacts with other parties or even coalitions. But that's not the point.
The point iss that erachand every one of thise MPs has an equal right to be heard, to contribute to a debate, to propose a motion, sit on a committee or to directly question a member of the Cabinet. Every Wednesday when Parliament is sitting, the Prime Minister must stand at the Dispatch Box and answer questions put to him or her by MPs. Any MP. These questions and the answers are heard, recorded and reported. The voices are heard. Also, the major parties can, indeed must, be disciplined in their voting and coherent in policy. The dreaded 'backbench rebellion' is never far away for a Govenment or Opposition that wanders or vacillates.
It's not perfect, by any means, but it has to be better than the constant obstructionism and destructive compromise that characterises the US system. Nor can it be trumped (let there be no groaning) by a Presidential veto or an autocratic Executive Order (known in every other country as a 'decree' or 'diktat').