people avidly collect the everyday Machin designed stamps of the queen,, but we have had the same design since 1967 ( at least the post office in the age of Queen Victoria varied the borders). But there is a (limited) alternatives of of buying a same queen stamp year on year from the post office counter, the regionals,
Regional stamps have been issued for decades but the newer issues reflect the growing self-government of the countries that make up the United Kingdom. I like the three dimensional effect of the design. I'll show the higher values. The first are those of the my home country England featuring the oak tree which in legend King Charles II hid to escape capture, its symbolism in heraldry is strength and endurance. Next we have the Tudor rose which combined the white rose of York and the red rose of Lancaster with the marriage of Henry VII and Elizabeth of York and has become one of the symbols of England.
The theme of all these stamps are national symbols and heraldry but Northern Ireland is politically sensitive so the Post Office has to perform a bit of a juggling act here so they have gone for on the 60p - a linen slip originally used to carry small personal items (The embroidery techniques is drawn threadwork). The 97p may look like a woven basket but it is a Belleek Pottery patterned porcelain. The vase portrayed is in the Belfast Museum.
Lastly is the 60p Welsh flower, the daffodil, this one created in Welsh slate by Ieuan Rees, 97p is the Prince of Wales feather in Welsh gold and silver by Rhiannon Evans.
I believe the stamps have a limited colour pallet to save costs. As far as the stamps are concerned they can cross all borders as they can be all used in any part of the UK.
An entry to Viridian Postcard's Sunday Stamps