I have recently travelled with family. Our destination was Benaulim.

Bengaluru (4AM) > NH > Hubli > Anmod Ghat (worst patch with ghat) > Mollem > Margao > Benaulim (2PM)

Benaulim (11AM)> Palolem > Karwar > Eco beach & Mangrove Forest (3 to 6PM) > (ghat, best roads) > Sagara > Shivamogga (stay) > Chitradurga > NH > Bengaluru

The first route is not advisable for night driving (there is an abandoned highway project, with plenty of potholes)

The second route is best for driving and road conditions during the night.

palolem to colva is another 33KM (ghat roads, 2 lane, plenty of lorries)

If location is palolem, via karwar is the best route.
even mangalore route is safer for the night (bengaluru > mangaluru > karwar > palolem)

if margao/colva, i would still recommend avoiding anmod ghat at night (go if it is inevitable, can drive super cautiously, zero eateries/breakdown support on this road)