I posted some long ass posts in another place a little while back on why I'm in favour of 'leave'
There will absolutely be downfalls if we leave but I think there will be plenty of upsides too.
For starters free movement AKA masses of unskilled workers coming in to the country when we absolutely do not need them is stupid.
An Australian style procedure for immigration would be excellent. Hell just recruiting the types of people we actually NEED would be fantastic.
Then there's the EU which is a complete mess for the most part. A couple of years ago the EU GDP growth rate was lower than any continent bar Antarctica
God I wish Brexiteers and other anti-EU figures would stop citing Australia's immigration policy as an example for Europe. Australia's immigration policy involves propping up makeshift camps and detention centers on neighboring pacific islands with few more provisions than food, water and very basic shelter. When the migrants protested they've been beaten by armed guards and locals, some to death. Women have been raped and impregnated by security staff and locals (the Australian government refused the impregnated victims C sections in Australian hospitals), children as young as 8 are attempting suicide and men are now self-immolating. Last year the government issued a full media ban on Christmas Island and Nauru. So they're fully aware of what they're doing here.
Detainees have two choices, accept resettlement in a third world country (the Aus government has spent $55M to resettle only ONE migrant in Cambodia with terminal health complications, untreatable in Cambodian hospitals) with no prospects of work or a normal life OR go back to the country from which you were fleeing persecution - many in the camps are Iranian political dissidents/ethnic minorities or they are ethnic Rohingya's who are systematically starved and slaughtered in Burma.
The atrocities happening on Nauru and Christmas Island detention centers now happen with such monotonous regularity that no one seems to care anymore. Both sides of Parliament spin it off as the evil necessary to solve a 'problem' which was never harming our society in the first place. This cruel policy actually costs more than processing and resettling migrants in Australia. Yes, standing up for basic human rights at less of a cost to a budget which is in deficit is actually now considered to be political suicide by both sides of politics.
Genuine asylum seekers who arrive in Australian waters by the only means available to them (unauthorized passage by boat) are never ever ever processed even if they're more than eligible for settlement (genuine claim for asylum, no criminal history, skilled worker). Instead, they're kicked from the queue forever, indefinitely detained and tortured until they return to the place they are fleeing. No review of their eligibility ever takes place to separate the wheat from the chaff as so many Brexiteers seem to believe. There is no pragmatism, just systematic cruelty.
I know the problem is different in Europe, but Australia's immigration policy since the turn of the millennium has been nothing but an election ploy designed to appeal to fear and bigotry. It's the biggest blight on the national conscience since the Stolen Generation. Even Anders Breivik paid homage to Australia's immigration policies in his manifesto. Britain have a terribly under regulated system of immigration, but Australia is not a good example for decent human beings to follow and I sincerely hope that the pendulum in Europe doesn't swing so far from the EU paradigm that it reverts to being the nationalistic clusterfuck it was 80 years ago.