The Nightstar Zoo

Whose to say Cindy didn't think of firing a trick shot before it was suggested? When the tactic was suggested she didn't say she hadn't thought of it, which she has in the past, she just expressed annoyance that she's being told to aim carefully again.

The people who do have upgrade fever, such as the UNS navy, are the ones who initially developed the Wyvern class six hundred years ago, or more Cindy might not have been a first production. Then they designed a better class and sold Cindy, and the Wyvern blueprints most likely, off to civilian contractors. She most likely then passed through multiple hands until settling with Sanctum Adroit who were practical enough to want a tried and true class, and involved in mostly police work so they didn't need the absolute best gunship around. Just one better than what any criminals would have. She was the ultimate big stick in Haven Hive for instance.

We can also see this when Cindy was plotting the counter missile fire in Eina'Afa. She was playing conservatively, but Tagon was immediately able to evaluate the situation and deal with it in a way she didn't really consider.

TAG/TAGII on the other hand was built to be a bona fide military genius. TAG destroyed itself saving Credomar in a span of time biologicals couldn't even process. TAGII could hold her own against an entire fleet, and outmaneuvered a battleplate after she went insane. Obviously not all AIs are equally effective tacticians.

Cindy has the basic AI advantages of speed and advanced sensory data, but she lacks battle experience and tactics. She can however execute any tactic she is given quickly and effectively. In every case we've seen she announced completion of the objective shortly after the tactic was suggested to her. She just isn't innovative enough to consider them herself.