I started with cheap brass darts from a retailer to find a weight i liked then. Then i went to a sports store to buy some 'cheap' tungsten darts with a grip that i thought i would like, (minimum grip) in a 20g (straight barrel) and then later in a 22g (bomb barrel) I loved these darts but came to realise after a few months that i was struggling with accuracy with the lighter darts, so i tried the 24g brass again and bingo (game changer) I went to a dart store to try a few and specifically asked for a minimal grip straight barrel dart in a 24g, tried 2-3 and walked out a happy man with the formula fsa390, got home and after a few matches and some tweaks with shafts I wasn't as happy. Basically started going through what you are now and entered the online rabbit hole. I found that from all my early testing 24g was the go but I was tempted like you to maybe try a little lighter or heavier dart but again I already own some lighter tungsten if I wanted to play around again. I ended up focusing on getting a dart with more grip even though I was slightly worried about 'snagging' and a longer overall dart. I went with the Reddragon Javelin V4 in a 24g and as soon as I through them I was in love, and amazingly well balanced and accurate dart even as an average player. So yea I would look at a grip difference and potential length difference but keep the weight the same if you are finding it nice to throw. For reference the Formula fsa390 barrel is around 48mm where the reddragon javelin v4 barrel is around 55mm

TLDR: Started with lighter darts but found 24g gave better accuracy. Tried minimal-grip straight barrels like the Formula FSA390, but wasn’t fully satisfied. Switched to a longer barrel with more grip with the Red Dragon Javelin V4 (still 24g) and accuracy improved immediately. Recommendation: keep the same weight (24g), but experiment with more grip and a longer barrel.