So, I know we're not doing like... a historical audit of each other. The game exists in a fun, fictional space where I hope nobody is going to police you on being poor or wealthy based on anything other than your say-so. I, personally, set us my character to be a retired cavalry Colonel, who suffered bad injuries in the Peninsula and was awarded a full-pay pension (instead of half) for services to the crown. He also has other sources of income: property, racehorse covers, investments, gambling, and probably also some inheritance (I haven't decided yet if the father who threatened to disinherit him merely did not support him during life, or if he also did not leave anything for my character when he died -- leaning toward there was some money when he died).
Anyway, I was just trying to get a handle on how much he would have won to afford the initial Cornet's commission (at least 2,000 pounds) and how much he would have earned on a Colonel's per diem, plus allowances for horses and troops. Because if the numbers were hugely disparate, I was going to invent some other income sources.
Blah blah blah, took me about 10 searches to find this website. Thought I would share it as a resource: https://www.napoleon-series.org/research/abstract/military/army/britain/pay/c_britpay1800.html
What I figured out for myself is that making 1 L 12 s 10 d / day, plus another 5 L 15 s 8 d / day for a battalion of 100 soldiers nets something like 2,780 pounds / year, before other income is considered. Pretty respectable! Mr. Bingley and Mr. Darcy were considered wealthy and obscenely wealthy to a non-titled gentleman's daughter, so I am pretty happy with allowing myself whatever additional fluff pads it out to the suitable-but-not-obscene level that I'm looking for.
I have no idea if I calculated the pension correctly (don't know if the extra pay for troops carried over, don't know what you had to do to qualify for full pay vs. half pay, don't know if it's a straight x365 calculation or if taxes have to come out, etc. etc.) And I'm not worrying about it!
But, having gone through the effort to answer the question to my own satisfaction, I figured I'd share the resource I found and start a space for anyone else who wants to put numbers to the madness (hello, my fellow Type As!)