Definitely. You are basically digging your own graveyard with the astronomical interest rate.

citibank ready credit is a debit card (not credit card) on a revolving checking facility. other than the ability of a debit card to swipe it during your retail shopping or using it in online purchase, you are also able to do fund transfers, issue cheques, or withdraw cash through atm without incurring cash withdrawal fee (unlike credit cards).

no problem, for more information you may refer to this link: http://www.citibank.com.my/english/readycredit/index.html
i would suggest mbb2cards and ocbc titanium as the best combo cash back cc at the moment. however, ocbc titanium is no longer open for new registration (until further notice), so perhaps you may go for mbb2cards first. since you are more towards installment plans, there are many participating merchants with mbb too.

for more information about the mbb2cards here: https://forum.lowyat.net/topic/2989298

yes, but need to use it wisely. 

yes, i suppose, since they have a minimum income requirement of rm24k/annum, as well as required documents such as epf/salary slips/be form/bank statements/ea form. and most importantly, this product is under citibank's overdraft & loans section.

oops, and this reminds me that we are off-topic from this thread discussing about credit card.