Extra club advice for a beginner

I’ve been playing again for about 18 months now after taking 20 years off and really enjoying it. Realised that I’ve been walking around with 13 clubs in the bag and was wondering if I should add another to the bag, even though I’ve only just realised, and if so, what do I go for to help me keep slowly bringing my handicap down. Current bag:

D, 3w, 4h, 5-S, 54, 60 and putter.

Any advice appreciated.

Thanks