Hi TS,
I suppose it depends what flavour you're after TS but, why not, give it a go!

I don't add brown cardamoms (or cloves) because I find their flavour a bit too "musky" and overpowering in rice.
White cumin seeds have a more subtle flavour than black so I'd personally use white in preference. Either way, I wouldn't use too many, unless you really like the taste (and crunchiness!) of cumin seeds.
Saffron can add a delicate flavour (and colour and fragrance), though I don't use it often. I use food colouring (and/or turmeric) for colour (and flavour in the case of turmeric) instead.
I use green cardamon pods (split) and some combination of Asian or European bay leaves, cassia bark or cinnamon stick, star anise, white cumin seeds, brown mustard seeds, fennel, panch phoran, curry leaves, pandan leaves and coriander stalks.
As I said, it really depends upon you're preference and the flavour you're after. I don't think there are any rigid rules to be obeyed here.
I think the key is to ensure that you don't use too many spices and that you gently fry them (I use butter ghee), for a minute or so, before adding the rice (coating it in the ghee) and then adding the water/milk (milk makes a big difference I find). Cooking by absorption will ensure that you retain most flavour but is more difficult to control than when cooking in excess water and draining (I do the latter mostly...it's far easier and quicker..and flavour loss is minimal, in my opinion).
PS: When I say "dry in an oven", I really mean a "warming drawer" set at a relatively low temperature (80-90C). Too hot and the rice will dry out too much. Too cool and you risk bacteria growth! I tend to spread the rice into a thin layer (e.g. in a baking tray) and let it "dry" in the fridge. Then I freeze it and/or microwave it, for 2 minutes, on high, before use.
Hope this helps TS
