Race types and competitiveness

[buyshirts]

Im am looking in a system i need to make a classification of races types.
I have started with 2 types
Handicaps and Non
In the handicap group i obviously have handicaps but i have put claimers and sellers.
In Non i have grouped together Maidens,Group, listed and other stakes races.
As i said im interested in competitiveness are these classifications right.
I will say i have gone through over 1000 races so i loath to change them unless really neccessary.