What options are there for a Patio Area?

This is our current situation.

We have a 'slab' patio which is 12 foot deep and 22 foot wide.
Although the area is usable, there are two problems.

First (less serious) problem is that it's too small, second problem is
that the ground is clay so there is a lot of 'heave' going on
throughout the seasons. If we re-lay the patio, in 6 months time it
would have gone bumpy again

The new surface needs to have the following characteristics.


Required:
1. Totally proof against heave
2. Cheap as possible (max budget is less than a thousand pounds,
South Coast UK prices)
3. Size is 17 foot deep, 22 foot wide (we do a lot of outside
entertaining)
4. DIY-able (SWMBO's Dad is a ex-builder, so we have the skills, if
not necessarily the brawn)
5. Easy to keep clean
6. Nice to stand on with bare feet
7. Able to withstand the heat (and mess) from our Cast Iron Chimnea
8. Will last 5 years minimum without major rebuilding
9. Slightly higher than the existing patio/grass area so that water
runs off rather than collect in a pool in the middle.


Nice-to-haves:
10. Able to complete in 80 man-hours or less
11. Retains heat from the mid-day sun.
12. Dog/baby/small Child Friendly
13. Ability to retro-fit floor lighting
14. Winter slipperiness is not a problem.


Do Like:
15. Railway Sleepers
16. Block Paving
17. Red House Bricks


Don't Like:
18. Commercially purchased Decking, it's too 'Ikea'
19. Not keen on pre-formed patio slabs


Our thoughts are so far a
20. Our budget is unrealistic.
21. A solid concrete base is needed


Um, I guess that's enough to be going on with. All comments
gratefully received!



Regards,
Steve
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