Crossings on the Sunbury, Frankston, Ringwood and Dandenong lines have been put at the front of the funding queue in the government's $5-$6 billion level crossing removal program, with $2.4 billion committed for 20 crossing removals over the next four years in Tuesday's budget.

But equally busy crossings on the overcrowded Werribee and Craigieburn lines – both of which run through Labor heartland – look likely to stay in place until after the next election.

And another key Labor promise – the $400-$600 million Mernda rail extension – is off to a slow start, with just $9 million for planning locked in in this budget.

The Andrews government's first budget contained few other public transport surprises, because most of the big-ticket items had already been revealed in recent days.

There is $1.5 billion to begin building the $9 billion-$11 billion Melbourne Metro rail tunnel, although $840 million of that funding will not kick in until 2018-19, when construction is planned to start.

And those on overcrowded peak-hour trains should not expect much short-term relief from the commuter crush, despite the $2 billion commitment to buy dozens of new trains and trams.

Less than a quarter of the $1.3 billion for 37 new high-capacity trains features in the forward estimates, and half of that money is four years away from being spent.

But then public transport patronage was flat in 2014-15, with Metro train trips barely increasing from 225.7 million in 2013-14 to 227.7 million journeys, well below expected growth.

Tram patronage was equally flat, rising from 176.4 million journeys to 178 million, while the number of bus trips taken barely moved, from 124.7 million journeys to 125.8 million.

The government attributed the negligible increase in patronage to "current economic conditions and [the] impact of historically low petrol prices on discretionary off-peak travel".

Reaction to the budget was mostly positive.

The Public Transport Users Association said there was strong investment in trains but less on offer for tram and bus users.

"Ours is a growing city, and we need a comprehensive public plan for upgrading our train, tram and bus services into a cohesive, fast, frequent network to get more people out of the traffic and keep Melbourne moving," spokesman Daniel Bowen said.

South Morang and Mernda Rail Alliance spokesman Darren Peters said the Andrews government had met its promise to fund planning works in its first budget and the alliance looked forward to seeing funding for construction in next year's budget.

Elsewhere, $360 million was committed to upgrading signalling on the Cranbourne-Pakenham rail corridor and $55.6 million went to a trial of high-capacity signalling on the Sandringham line that, if successful, could trigger a huge boost to rail capacity.

A trial of 24-hour public transport on weekends will begin in January, with $50 million committed over the next two years.

The government has committed $15 million to extending and reinstating bus routes, including Brunswick's tiny Hope Street route, and a $5 million bus interchange will be built at Huntingdale, an important bus-train link for Monash University students and staff that has long suffered from poor connectivity.

Taxi licence-holders will be able to claim from a $4 million hardship fund for those most heavily disadvantaged by the former Coalition government's industry overhaul.

Meanwhile, the budget papers reveal that the total cost of the Regional Rail Line project – a 45-kilometre rail link for V/Line trains between West Werribee and Southern Cross Station due to open in June – has fallen from $4.1 billion to $3.65 billion.