Two things:
1) People would bitch about tires not lasting the distance of like 10-15 laps and creating a mockery of racing. Pirelli has come under fire for being unable to provide durable tires before (they can provide them ofc but were asked by FIA to provide less durable to mirror that Canadian GP from 2011). Two or three blowouts during a single race weekend and it's a horrible look for Pirelli with drivers bitching about safety. You can take it to the bank.
2) Hah! Pitstops were removed because people complained drivers are unwilling to make a pass on the track and only wait for the pitstops to jump their opponents! So this was supposed to aide overtaking but now it's fuel-saving and undercut strategy which doesn't help passing either. These races are run from pit wall with each car having like zillion engine maps & fuel consumption modes, the driver no longer controls the fuel with clutch/gas pedal alone. IndyCar still has that old school technique but F1 is all about electronics mode controlled from pit wall.
Edit: I forgot to mention the supposed "cost saving" has limited teams to three engines per season before a penalty comes. So they're going ultra safe in first place and ain't gonna risk blowing an engine to have a driver finish 4th instead of 5th! Plus most engine changes are done in strategic spots, nobody's gonna put a fresh engine ahead of a technical track like Budapest but ahead of Monza? Most likely! You need a complete horror show like McLaren-Honda to ignore all that thinking but it's a horrible look for the company and the entire thing just blows up in your face. Fans might take cheap shots at this but some big heads are downright mad to see a millions of investements go down with a myriad of 20+ places grid penalties every other weekend!
First thing to aid the racing is to take the weight off the cars. At least 150-200 kg. F1 is turbo-powered tanks racing, increasing the power does nothing if weight goes up at similar or greater rate. The power-to-weight ratio is horribly skewed and is one of the chief reasons why we have so little passing without the obvious DRS gimmick.