Hi Keemanan and welcome to the forum.
I'm not sure adding curry powder will improve your traditional recipes.
The way I see it is this: To get the BIR flavour we are used to in this country the chefs use a spice mix that contains predominantly in descending quantity order:
Turmeric
Corriander
Cumin
Curry powder
Paprika
The curry powder only amounts to about 17% of a typical BIR spice mix.
I believe it is added by the chefs to add a little depth of flavour as commercial curry powder often contains many more spices such as curry leaves, fennel, cardamom etc.
I also think the ratio of the main players (Turmeric/Corriander/Cumin/Paprika) in most commercial curry powders does not match what the BIR chefs use in the UK so you would probably never get a good BIR flavour match if you just used curry powder on it's own.
Regarding base sauce I think most of us on here use it but not everybody.
I'm interested in traditional Indian cooking too so if you have any good recipes please post them.
Cheers,
Paul.