Absolutely! These are some amazing destinations in India. Here are the travel tips for your journey.

Best Time to Visit:
1. Goa:
The ideal time would be during winters, from November till February, when the weather is not very hot and is quite pleasant.
2. Mahabaleshwar:
This can be visited all-round the year, but it's particularly beautiful during the monsoon (June to September) and winter (December to February) seasons.
3. Mumbai:
The best time to visit is between October and March, when the weather is delightful.

Route and Accessibility:
1. Goa:
Goa is well connected by airways, railways and roadways. The nearest airport is Dabolim Airport.
2. Mahabaleshwar:
There are several buses from Mumbai and Pune. Alternatively, you can also drive from Mumbai (6 hours).
3. Mumbai:
Mumbai is a major city and is well connected both domestically and internationally.

Altitude and Acclimatization:
None of these places are at high altitudes, so no need to worry about acclimatization here.

Accommodation and Booking:
Make sure to book your accommodations in advance, especially if you're visiting during peak seasons. There are various options ranging from budget to luxury accommodations.

Clothing and Essentials:
1. Goa:
Pack light cotton clothing, swimwear, beach essentials, sunscreen, and hats.
2. Mahabaleshwar:
Light clothing for summer and warm for winter. Comfortable shoes for sightseeing.
3. Mumbai:
Light cotton clothes are ideal. Carry a good pair of shoes for walking and sightseeing.

Health and Safety:
All these places are quite safe. However, it is recommended to follow general safety measures like taking care of your belongings and being aware of your surroundings.

Local Etiquette and Respect:
In all these places, locals appreciate it when tourists respect their culture and traditions - especially in religious places. Dress modestly while visiting temples.