Also, it's not wise to purposely go cancel your underused/underutilised ccs. Here's why. 
 
Over the past 3 months, the banks all either gave me free money or invited me to apply for ccs with cash rebates.
Maybank invited me to apply for their new new cc and gave me $30.
OCBC smsed me to swipe any 3 transactions of any amount on my nv-used-b4 titanium cc and gave me can'tremember $20 or $30.
DBS reminded me to activate my replaced formerly-ANZ card and gave me can'tremember $30 or $50.
SCB gave me $30 or $50 if I applied for the Unlimited cc.
AMEX gave me $80 NTUC vouchers if I applied a card.
Still got HSBC $140 if you get their Advance card, but then this one you need to swipe $600 first.
Not bad right?