Marathi is a language spoken by some 68 million people in India. The mr.wikipedia has some 15.195 articles, the mr.wiktionary has 267 articles. I am not aware of other WMF projects. I am not aware of other projects in Marathi outside of the WMF.
73.99% of the most important MediaWiki messages for Marathi are now localised. As not all of the most important messages of MediaWiki, MediaWiki is not really useful out of the box. One of the ways the localisation can be improved, is by importing messages from projects. SPQRobin imported some 500 more messages from the mr.wikipedia and after running several sanitizing scripts, they were committed.
SPQRobin does not speak Marathi but it is probable that he did a great job. It would be good if someone has a look at the Marathi messages. Hopefully not only to check the existing messages, but also to work on the messages that still need to be done.
Importing from a project is one of the obvious methods of enriching the MediaWiki localisation. Proof reading the localisation is important and will improve the quality of the MediaWiki experience. Hopefully someone will come along and do this for Marathi
With the BetaWiki developers actively looking at improving the MediaWiki localisation, allowing MediaWiki to already have five separate forms for a plural, it may be that languages like Marathi or Hindi have their own needs. :)