Plus they are hardly ever going the speed limit, the need to stop is less. However, if they ever do need to stop, they have a device called the floormat which apparently blocks the brake pedal, further saving the pads from wear.

OP said:
"The oil place checked the quantity and quality of the various fluids" So you serviced the car at an Oil Place? Is an Oil Place like a jiffy lube ?? I think you'd be better served by another Asian car.. New Genesis G70 or KIA Stinger..Acura TLX, Infiniti, Lexus

The one real maintenance on the prius at 120k miles was done at the dealership. Within reason, I am willing to spend a bit more on maintenance on an A4... but am still a bit unclear, are these additional costs due to the way an Audi is typically driven, or due to the way it is designed? And from reading a variety of posts, it seems like some think the A4 is a Ferrari, rather than a comfortable family sedan...

You are way overthinking this. The Audi A4 is a solid reliable car that will treat you well if you are conscious about doing the same in return.

Follow the maintenance intervals by either a) bringing it into your local Audi dealership b) finding a reputable independent shop that specializes in VAG cars or c) do the work yourself.

I personally bring my B9 to an indie shop every 5k miles for an oil change and use AudiCare for standard interval servicing.

In complete honesty, if you want to compare an Audi A4 and a Prius, you have no business buying an Audi. I have owned both. They could not be more different in every aspect

Will the 5K oil change provide additional benefits as compared to the 10k/1 year oil change?

I have Audicare for regular maintenance.

Actually, that was in the past, the future is looking A4/A5, Lexus nx300h, or the simple safe, but dull choice of a camry hybrid... and looking like I can get the used 2018 prestige CPO with <10k miles for about same price as top equipped camry or 2018 NX.

You always have the option to lease. Throw in AudiCare which bumps the residual up 1% and your maintenance will be covered for the period of your lease. 3 years from you can then turn it in for the new, latest and greatest A4.

There are threads upon threads on this already. It’s entirely up to you the owner. If I leased, I would go every 10k. However I buy my cars and feel that 5k is as long as I am comfortable going on the same oil based on my driving conditions.

I'm with you on the Asian cars. Coming from Honda's which seem to be bullet proof, Audi's tend to be fussy or finicky if you will. I agree the brake fluid would likely go 100,000 miles with no issues. Plugs probably won't make a huge performance issue so I would go longer as well. However, if you want to follow the regime you can. Most of the people here have deep pockets to pay repairs or add on's and love the performance of the Audi's. When they work, they work very well. When they don't they will cost you $$$. It's my experience with Audi's so far anyway with a number of issues and less than 60,000 miles on the odometer. They are like thoroughbred horses in a way. Sleek, fast but make you have a vet on call just in case. Don't listen to the haters here.

I think the future is electric and so does Audi from what I read going electric and all. Test drove a Tesla 3 last week. Blows my A4 away from a 0-60 perspective. Less maintenance too. But as a new product, probably wait a couple years before you dive in. I think there will always be a niche for petroleum powered cars well into the future and Audi's will be there in some form.