For me the best outcome is with moderate-high Dopamine AND moderate-high Serotonin at the same time.
I tried Tyrosine alone and loved it - for 3-5 days, then things became strange: sleep, angry, ***hole - crash.
After all this Serotonin-Banging in the Ray Peat Sphere I was scrared to use Tryptophan or 5HTP.
Until 2 Month ago - I combined Tyrosine and Tryp in the famous 10:1 Ratio and feel very good/natural with this: Energy and Focus is up and I also feel nice/jovial and smart. Also sleep is ok.
tyrosine can easily raise adrenaline especially in the absence of sunlight on the eye, there was a thread about this some time ago
that being said, i agree with your conclusion that some degree of serotonin seems neccessary to remain functional or even thrive in a typical modern setting (office, traffic, public transport for example)
now i might be completely wrong thinking its due to low serotonin/high dopamine but whenever i overdo it with things like low tryptophan diet, metergoline, glycine, aspirin, coffee etc. i become very easily overwhelmed with life and everyday situations. feels like all the filters are off so to speak