28 should stay the way it is, at
least for the Tampines to Bedok part.
46 is a quite well-planned route. I see a few major high demand
segments after DTL3 opens.
1) Tampines Int > St 83 / Ave 3 (291 fleet cut?)
2) Tampines West MRT > St 83 / Ave 3
3) Bedok Reservoir MRT > Bedok North Blk 85 and beyond
291 can reduce 2 buses. Too many buses for 291.
Actually 46 could have looped around Tampines town for eg:
Tampines Ave 5 > Tampines Ave 4 > Tampines Ave 7 >
Tampines Concourse > Tampines Ave 4 and back.
This way it would have also connected important amenities such
as Century Square mall, the new stadium and hawker center along ave
5 (but bus will not be calling this stop) and Tampines Regional
Library.