Here is my list:
171 --> Yishun Interchange <> Beauty World (loop)
67 --> Tampines Interchange <> Newton Circus (loop)
986 --> CCK Interchange <> Beauty World (loop)
new service replacing sv 67
between CCK and Upper Bukit Timah road
Future
rationalizations:
sv 66 once DTL3 is up (Bedok -> Newton Circus (loop), new
service to replace Jurong East - Beauty World sector). sv 700 to be
extended/modified. sv 961 to be replaced by another service between
Lor 1 and Queensway but deleted between Woodlands and Queensway
(alternative: 170, 960).
Both your amended 171 and 67 would end up to be too long though,
very risky for bunching. 67 could probably terminate at Little
India, St Michael or Queen St terminals. 171 would be better if
amended to terminate at Jurong East, either via 41 or 66's route or
simply express until Toh Guan.