A few months ago, I bought a 2015 Subaru Outback and the front left caliper was acting up, so I had a mechanic check it out. The mechanic recommended replacing the two front calipers (they were pretty rusty), the front-left brake hose, and then just greasing the rear caliper pistons.

I'm no longer hearing any weird noises now from the front-left and the brakes feel much smoother, but there's a couple differences that are throwing me off. The distance the brake pedal needs to be depressed before the brakes start to bite feels a lot longer now. I've also noticed a kind of hysteresis, where if I apply the brakes twice within a second or two, the second time I apply them, they'll start biting earlier.

Should I get the brake fluid replaced / bled? Could air in the brake lines explain this behaviour? (I assumed air in brakes line would had to have been bled but it's not explicitly listed on the bill I got.) Any other explanations?

The mechanic did paint the calipers too, just to delay rust, and there was a bit of overspray on the rotors, but I'm sure it got instantly scraped off by the brake pad.

Any advice would be appreciated!

Edit: To clarify, I did not get the pads replaced. The inspection done when I bought the car showed about 50% life left on the pads.

Follow up: You folks were right - They bled the brakes and the car felt like 90% better. They said the master brake cylinder might have been leaking a bit so they offered to replace it with no labor charge, so I sprang for that too, but it's hard to tell if that made any difference. Either way, it feels back to normal now, so thanks for your advice!