Bold Seagull
strong and stable with me, or...
It's a game of opinions...
I was staggered how good my 105 5800 was when compared to my ageing sora groupset. In my experience money spent on cycling stuff is always money well spent. Oh yes, a good set of wheels would be good too. However, I could see that if you put a new groupset and wheels on your bike then you may want some new pedals, saddle, bars, frame, forks.... Oh.
When you did your ageing Sora upgrade, did you also do cables and housings at the same time? I reckon the new cables and housings made a lot of the difference in my case. You don't notice the deterioration of cables and housings over time, and I must have left mine 4 years or so, it is like having a new groupset just doing them sometimes.