Just to mention that the FTSE250 index (covering the 101st to 350th biggest companies) is now at a record high. A few years ago it was about the same as the FTSE100 but now it is far ahead, around 7300 against 5050.
FTSE250 companies tend to be less influenced by global markets as typically they have most of thier business in the UK. UK banks are in the FTSE100 not FTSE250.
Years ago a sunk loads of money into tech stocks and FTSE250 stocks - some did very well and some did very badly !!!
Obviously although the FTSE250 has been outperforming the FTSE100 for years there is no guarantee that it will continue this way.