india in mid april...advice

my adult family are spending 10 days in mumbai and surroundings in mid april...we thought of a two or three dasy in mumbai staying at shelley's hotel, two nights in the hill station of matheran probably at the regal and a few days in goa. Here we want to stay at Kerkar retreat. What do you more experienced travellers think. How hot will it be and any suggestions for what we have choesen for accommodation. We thought we'd take the train to goa, one way overnight, so we could see the countryside a bit

thanks for any info
margo