Things to check in possible issue order
1. Always change any wishbone upper or lower in pairs regardless of condition
, bushes are always weaker in an old wishbone which accentuates any difference because the new wishbone is tighter. You start to get wandering and vagueness.
2. Also check your anti-roll bar for lateral movement (side to side). It may have no play up and down so no knocks or rattles but a firm tug towards you and away from you either side and your clamps that tighten on the inner bushes could be loose enough to do this.
3. Swap wheels and tyres front to rear and see if that improves the matter and double check pressures. If you had these tyre on the front previous to any suspension work, they will have worn slightly unevenly as a result. They won't continue to get any worse after the suspension has been replaced and set up but they certainly won't wear evenly afterwards either, they will continue on to wear the same way... Like an old brake pad on a worn disc, you replace the disc but the old pad is still worn in that pattern and will be for a long, long time, unfortunately tyre don't wear in eventually.
4. Power steering fluid, how clean is it? it should be cherry red and changed every two years.
If its really dark or black its time to disconnect the rack union and drain it... Replace the fluid and bleed by turning lock to lock with the engine running with the filler cap off, keeping an eye and topping up accordingly. PAS fluid over time can loose its compression properties so can cause uneven feel on turning and possible "pulsing" when it gets really bad.
5. Check your track rod ends, jack the car up and turn the steering via the road wheel while keeping a hand on the track rod end, feel for any stiff clicks or bumps in its movement, it should be a smooth even movement. Now place a pry/crow bar under the tread of the tyre and use it to lever the wheel up and down while feeling for play in the track rod end, it should be very little play and no knocking, clicking or a jumping sensation.