I share your concerns, particularly #2.
I too have experienced totally inexplicable scenarios in which my defender can’t catch a dribbling attacker of only modest pace attributes (even over 30-40 yards), while my Gareth Bale (one of the fastest players in the game) gets inexplicably caught from behind. The only thing I can conclude is that (similar to FC 25) FC Mobile employs an algorithm that randomly slows attackers on potential breakaways. The rationale seems to be an effort to level the playing field for less skilled users and/or users with poorer players, but the effect can be quite obvious (and infuriating) at times. Thus, those of us with better (faster) players experience these effects more noticeably than someone with, say, an OVR 108 team of second-tier “bargain” players.