Government asked to support Landlords to encourage longer tenancies

The first time I was a landlord I was a 'deliberate' landlord. I invested for the long term in a buy-to-let with the intention of paying for my children's education. I changed my mind and divested just before Northern Rock because I was aware that Gordon Brown had caused an economic collapse based on a housing bubble (and he must have known that that is what he was doing). So I sold the property, my wife and I declared the capital gains and paid it even though we could have lied and declared the property as my Principle Private Residence, just like all those MPs did - it was the year of the MP expenses scandal.
This time around I'm an accidental landlord. I held on to a property to pay for my elderly mother's dementia care and ultimately to develop it in order to mitigate against the financial consequences of that for me and my children. At the moment I'm renting that to a family of four children and my long term aim is to develop the property, for the benefit of my family.
My present tenants make a mess. Last summer I had to visit the property to do some work and even though the property has plenty of bins (double the usual number) all the bins were full to overflowing with unsorted rubbish and there were black bags full of unsorted rubbish next to the bins. The foxes had torn these open and the contents were spilling and blowing out into the neighbour's garden. There was the usual mass of flies and maggots.
The reason why this rubbish was there is because the council will not collect unsorted rubbish. It's hard to understand why this would happen because what you can and cannot put into each bin is clearly written in English on the top of the bin. The tenant speaks English. I cleared the rubbish to avoid upsetting the neighbours, who I have known for years.
The tenant has four children. They make a mess. I've got kids so I understand this. The hand prints on the walls, the drawing on the walls; the posters stuck up with blue tack. I understand why kids don't always do what you tell them to. I've told the tenants that my long term aim is to develop the property, I won't be taking a view of the mess until I see what state it is in when they finally vacate; I have told the agent that I'm aware of the mess but if the tenants don't do any serious damage if they continue to pay the rent on time and in full and end up staying there until I develop it may not matter, because I will be pulling the property apart anyway. I have openly discussed my development plans with the tenant and when I get closer to the point where I will develop I'll be giving more than the statutory notice so they have time to plan to move somewhere convenient for schools etc. The tenants actually have two buy-to-let properties of their own but neither has sufficient space for their family at the moment; if they are there long enough and two of the children fly the nest they may be able to move back into one of their other properties. I keep the property well-maintained and on the advice of my agent I haven't hiked the rent up to minimise the risk of void periods.
So what I'm doing is what's right for my family. And what I'm doing benefits my tenants family. They are a long way from being perfect tenants - but paying the rent on time and in full makes a difference. Some of the other stuff I can live with, even though I should not have to.
And that leaves me with the question of 'encouraging long-term tenancies'. Any property is an investment. My intention is to improve my property as a long term investment i.e. to invest in it, which is what some government departments want - to improve our housing stock. Although I have held the rent down I have previously rented the property at a higher price and accepted the void periods. My last tenants were there because their own property had been damaged by flooding and they needed somewhere for six months. They weren't perfect tenants either. Their insurance company paid for the rent but they left the property in a right mess.
So at the moment I actually have 'long-term' tenants. These 'long-term' tenants just need the property for the period before their kids fly the nest; not for ever, their needs will change - once it's only Mr. and Mrs. Tenant they won't need a property that big. I've often found it odd that some Council tenants are allowed to stay in large properties indefinitely even though their children have already flown the nest and pay rent below what you'd have to pay to service a mortgage. And they have 'right to buy' - so they buy and sell on and take a nice little after tax gift from the tax payer.
At the moment I can live with my 'long-term tenants' despite the mess. But if the government were to introduce anything along the lines of rent-controls, 'right to buy' or anything that stopped me doing what I need to do for my family then I would have no option but to kick the tenants out. If the government did what it did at short notice I'd have no option but to kick the tenants out at short notice even though my preferred option is to give them plenty of notice to make plans for their children.
So the government needs to think very carefully about how it encourages 'long-term tenancies' because it could do a lot of damage.