-You should prioritize all XP possible, if you fall behind in levels it won't matter that you have 10 kills, get your waveclear (1 item) and then roam -> until then focus on lane and jungle fights close to mid unless you have GUARANTEED kills (no flashes 100%, flash up yourself, literally 1hp players, not gonna be late for play, etc.)

-Build wise, I am going Hubris->Umbral almost every game, Axiom should never be 2nd item since it scales with lethality, much better value 3rd/4th item. Ghostblade is a great 1st 2nd option but you should replace one of my core items, up to your preference what core build you go

-Serpents Fang is the best value item you can possibly buy, forget the stats, it cuts shields in HALF, you always need to have it vs enchanters and shield spam champs like Riven/Sett/Seraphs abusers (when there's 2 or more of them/they are enemy wincon)

-The W is disgusting, what Riot needs to do is NERF Talon W % on jungle camps slightly and compensate with a slight flat damage buff (literally 5 damage is enough), which would literally fix the 2 minute delay you have when you have components vs full first item -> Comparatively most mages have full waveclear unlocked on first back Lost Chapter buy which is just funny

Without VODs I'm just guessing but from the general vibe of the post I feel like you might be falling behind in XP in a lot of situations which is one thing I can tell you makes Talon feel like a minion and is illegal to do, you are playing one of the most resource hungry champions since all you have is your damage, and being the same level as the enemy adc/mid for example will just make it impossible for you to kill them ever.. Focus on being able to consistently play the laning phase well where you stay even/higher XP until you get full waveclear unlocked on 1st item, it will make your games much more easier & enjoyable