Googling “turning steering wheel increase idle rpm” yields:
Most modern car automatically increase the idle rpm to compensate for the extra load when the steering wheel is turned. Aug 29, 2021
May not apply to OP’s specific car of course.
Did you replace 2 RFT (run flat tires) with 2 non run flat tires and now running 2 RTF AND 2 reg tires or vice versa???
Swapped em round, it’s 2 regular tyres in the front and 2 RFT’s in the back
RFTs(run flat) tend to have stiffer construction to compensate for loss of pressure.
They tend to be less compliant over bumps, course pavement, and in turns.
Standard(standard load, non-RF) are ‘softer’, to varying degrees, and their contact patch(with the road) size varies more with differences in tire pressure and shape with how hard you go in and out of turns.
Standard tires = more pneumatic trail(think front wheels on a supermarket cart).
This is what contributes to self-aligning torque on the front(steer) tires - part of what helps the steering wheel center itself coming out of a turn, or if you let go of it. It helps, along with Caster and other alignment angles, to keep your vehicle going straight without constant correction - steering inputs - from the driver.
So generally, lower tire pressures, softer rubber compound, and, less power steering boost, contribute to heavier, greater steering feel.
Higher pressures, or heavier stiffer rubber compound, or higher power assist boost, contribute to lighter, lesser steering feel, sometimes almost to the point where aligning torque is canceled out, and you must center the wheels yourself…!
This is partly why you saw much lower recommended tire pressures for cars from the 1940s to '60s, when most vehicles rode on rocks- AHEM - bias-ply tires. 
I might be off on this next point, but, it might be better to have all of one type tire or the other - all standard or all RF - on the car.
Some cars, particularly those with EPAS(electric power assist) steering, might have steering or drive modes to select from. Comfort or Normal might feel too soft, numb, where as Sport or Track(think: Acura NSX S-series) will usually feel heavier(lower assist level), and the steering natural self-centering will be stronger - the way I prefer.
Apologies for the book…! I hope various readers here will find parts of it informative. 
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Basically most RFT (all Bridgestone’s) tires have a very thick sidewall to support the weight of the vehicle with zero air pressure (for X amount of miles and speed) where as a non RTF has a very thin sidewall compared… Your suspension (struts/shocks) are designed to run on that stiff sidewall for steering response and handling, conventional tires do not have run-flat capability and the handling characteristics of the vehicle with these tires may be different. Mix and match your tires and you will only end up with imbalanced handling…
BTW, we could never replace a single or pair of RTF tire(s) with a non RTF tire(s) unless it was an emergency and temporary and we made the customer sign off on it…
Now you have 1st hand experience with what happens when you mix RFT with non RFT tires and how it effects the way a vehicle drives/handles… You need to get all 4 either RFT or NON RFT tires…
And if you go the NON RFT way, just remember that you probably don’t have a jack, lug wrench, a spare tire or anything else needed when/if you have a flat tire…
This is from Bridgestone:
CAN I REPLACE RUN FLAT TIRES WITH REGULAR TIRES?
Yes, you can replace four run-flat tires with four conventional tires as long as they meet your vehicle’s manufacturer recommendations.
Keep in mind that different tires are designed to deliver different results. A run-flat tire is designed to keep a vehicle traveling safely and under control for a limited distance, even after a puncture. RFTs don’t rely on air pressure to maintain their shape and capabilities over a limited distance.
Compared to a standard tire, a run-flat tire has a thicker, more reinforced sidewall made of special heat-resistant rubber to support the weight of the vehicle and passengers for a limited distance, even if the tire has little to no air pressure.