I'm employed in my second year of practice in a private practice in a multispecialty group in a mid-sized town and make $245k, which is on the higher end but still typical. Any of the "cognitive" specialties (ID, endo, rheum, non-CC pulm) are going to be similar. You might expect a range $200-275k depending on the desirability of the location and how hard it is to recruit people--you're going to be on the lower end in all the places new graduates typically want to live like SF, NYC, Boston, Austin, etc because you're a dime a dozen. Pay will be much higher in rural and less "desirable" areas. Pay will also tend to increase as you get more experience and more seniority, particularly in a physician owned group. I am aware of rheumatologists making mid-$400k+ but they work like dogs and make some... "interesting"... patient care and care utilization choices. Participating in clinical research is another income opportunity and is in high demand, but carries a whole separate set of considerations and headaches with it on top of your day to day practice.
Lifestyle is more or less what you want it to be. I'm here from about 8-6:30pm most days, seeing patients from about 8:30-5 with the rest of the time doing paperwork and reviewing results, with a hospital consult maybe twice a month. I'll typically see 18-24 patients in a day. I take call for my own patients during the week, and take about 1:6 weekends. In a whole month (including a weekend) I probably get 3 phone calls after hours and in 85% of cases the answer is either "call your usual rheumatologist on Monday" or "go to the ER". If you are in a partnership track, or an RVU-based employment model with production bonuses, you could choose to work more or less than me and your income would vary accordingly.
Procedures are not a cash cow in rheumatology. If you want to make more money your main tool is increasing E&M. Joint injections pay a little but they're sort of an adjunct to most of what you do as a rheumatologist, which is making long-term treatment plans, assessing disease activity, and monitoring for treatment toxicity. For a while in the late 90's-early 00's infusions were a bonanza but now most practices make a small profit or just break even. CMMS has been cutting reimbursements on drugs, and now there is a proposed demonstration plan where reimbursement of drug costs will be cut to 1-3% of purchase price, which in many locations depending on business taxes, overhead, etc will put many practices underwater on infusions and they will stop providing them. Eventually I suspect most patients will be going to oncology practices, hospitals, or commercial infusion centers as are being started by Walgreen's etc to get their infusions because docs will be losing money trying to provide them for their patients.