When you do your PPL you will be given a Single Engine Piston class rating (SEP). If you do this on aeroplanes, you'll get a PPL(A). This allows you to fly most Single Engined Piston powered aircraft. Note that for helicopters this would be different. I think that what you are referring to is the class rating required for bigger, commercial aircraft. Because each aircraft is highly complex in its systems and operations, you can't just jump from one to the next. Therefore you have to do a type rating. The type rating is the training to get you competent and approved to fly one particular aeroplane, for example the A320, or a G550, or Dash8 etc. These cost a lot of money, from around £20k upwards. Some companies pay for this for you, others expect you to fund it yourself.
But way before you need to worry about that, you'll need to worry about the basic licence. If you go Integrated, course fees in the UK are £80-90k. Plus accommodation for at least 12 months, and living expenses. Then the type rating, if you choose to buy it, goes on top. Or, if you go modular, you can probably get qualified for £50-60k to which you could add a type rating.
PPL, I may be biased, but Leicestershire Aero Club is not about to go bust. It's not just a school / factory, so doesn't run on the same model as the likes of Cabair or PTC. I can wholeheartedly recommend the PPL, Night Rating, IMC and CPL training. For Multi-engine and Instrument Rating, there isn't anywhere in Leicestershire itself but again I can recommend Central Flight Training at Tatenhill which is not far away.
There are no restrictions, as far as I aware, rewarding what you use to hour build. It does have to be a real aeroplane, not a simulator. It's down to you to use those hours to best effect. There are plenty of threads on hour building on here. Use the search facility... Similarly you'll find lots of info if you search for ground school options for ATPL theory. Several friends have used ProPilot at Coventry, I used CATS, both no problem passing first time.