I suggest you explore that avenue. It's reasonable that the amounts mentioned be deducted to the principal loan of 60k because that was his/her payments for the principal amount especially that no interest has been agreed upon in writing. You can only enforce an interest higher than the one provided for by law (i.e., 6% per annum) when the same is agreed upon in writing.
Grab the opportunity while your debtor is still open to paying her loan. If she can only afford to pay 4k a month, then that's reasonable than nothing. However, you should demand interest on the outstanding balance. You can make counter-offer. You can demand your earlier agreement of 10% per annum. Say for example for the 60k loan, if you agreed that the same be payable in 2 years the total obligation would be 72k then less her total payments made. The difference will be the amount to be paid in equal monthly installments. Divide the amount to 24 and the quotient will be her monthly installment. You can also demand that the entire amount be covered by 24 post-dated checks representing the monthly installments. In addition, should her checks be dishonored the unpaid installment will incur interest at the rate of 6% per month until fully paid. Remember also to put a condition that in case of default of 2 consecutive monthly installments, the whole obligation shall become due and demandable without any need of demand.
If you will reject the offer and wants to go to court, consider the expenses, time, and effort that goes with it compared to being open to negotiation and presenting your counter-offer during the brgy conciliation. Although your case is covered under the small claims case where no lawyer is needed, you will still be required to produce supporting documents to prove the loan, your agreement of 10% return of investment, etc. You also need to attend the hearing/s and should you fail to do so, the court will dismiss your case or worse dismissed it with prejudice.
Your debtor may also hide by relocating to another place that will make it hard for you to collect. If I were you, I would explore a compromise agreement at the brgy level.
Good luck and God bless