The money you guys get for young whitetail, the fact they twin & the young age you sell them, would make it pretty hard for other species to compete.
We had prices like that once,but they proved unsustainable.I can buy good breeding red deer hinds for $300 ($2000 25 years ago) & good fallow does for $100 now.
Hog deer are still the best return at about $1000 per hind but this is dropping fast as they become over supplied.
Sambar,rusa & chital are so abundent in the wild & we have almost no closed seasons on these species so they aren't worth much.Sambar also take 10 years to mature & weigh 600lbs,so you'd better have grass & browse to feed them.They'll also go you in the yards,& have killed a few farmers (most likely me to one day as they're really my favourite deer & I like to work "with" them).
I have thousands of straws in the tank (some going back to the 80's from big "name" boys from around the world) but why use them when a great stag is $1000 or less (I paid $300 for the red stag I'm using this year) & live breeding is easier.
Unlike whitetail ,red deer pedegree can be traced back to about 1618 in some lines,& they've seen the bell curve rise & fall a few times.
What your earning from whitetail is fantastic.
Getting other species will be great fun & increase your stockmanship & skills more than you could imagine,but are the returns there?
Hunters from the USA are interested in our rusa down here.Although tropical they survive in parks in the UK & mature young (6 to 7 years) so they could be an option if they are avaliable.
Good to see some optimism & investment in deer however you choose.
Good luck
Sharkey