Choose club openings by the kind of middlegame decisions you handle well and the weaknesses you want to improve. Review several recent games before changing your repertoire. Were you short of space, unsure about a pawn break, or surprised by a forcing line? The answer may point to a specific lesson within your existing opening rather than a need to replace it.
Build a stable core with enough variety to teach you different structures. For example, a Queen's Gambit repertoire can introduce central tension, isolated pawns and minority attacks. A Caro-Kann repertoire exposes you to both closed Advance positions and more open exchanges. Learn the plans that recur within those structures, then decide which variations fit your practical preferences.
Balance preparation with the time control you normally play. In rapid games, familiarity with common decisions can save time. In longer games, you have more opportunity to calculate but still need reliable starting knowledge. Avoid selecting a sharp variation solely for its surprise value if you cannot explain what happens after the opponent finds a good reply.
Keep a short review log for each opening: one model position, one recurring mistake and the next line to practise. Add depth where opponents repeatedly test you. Review quieter branches as well as dramatic attacks, because club games often leave theory through ordinary developing moves. Consistency across a season gives you better evidence about an opening than the result of a single evening.
Try this at the board
Choose one recent game and classify your first opening difficulty as recall, calculation or understanding.