vinodh wrote:I am kinda looking for a good mix of the above (I'll ignore Tantra & Sadhan-s for now). Perhaps, the content more inclined towards Sutras, Avadanas & Shastras.
First I would try some of the very short sūtras, such as the Prajñāpāramitāhṛdaya, the Pratītyasamutpāda, the Pratītyasamutpādādivibhaṅganirdeśa, & the Nairātmyaparipṛcchā (all transliterated on the GRETIL site linked by Ratna). These are philosophically interesting, grammatically easy, full of fundamental Buddhist vocabulary, and no more than a page or two in length.
Some interesting, slightly longer sūtras, progressively more difficult: Śālistamba, Vajracchedika, Mahākarmavibhanga.
The Buddhist Hybrid Sanskrit Reader—already mentioned above—is a good introduction to prose narrative and gāthās in longer sūtras, with manageable selections from the Lalitavistara, Mahāvastu, Saddharmapuṇḍarīka, and some others.
For śāstra, Nāgārjuna's Pratityasamutpādahṛdayakārikā + vyākhyāna is the shortest & easiest complete śāstra (i.e. root verses + commentary). Then Vasubandhu's Vijñaptimātratāsiddhi with commentary, then the Triṃśikāvijñaptikārikā with Sthiramati's bhāṣya. Then Vasubandhu's commentary on the Madhyāntavibhāga. Even if you aren't particularly interested in yogacāra, I think it's best to start with these, as they're short and Vasubandhu has a concise yet clear style.
Aśvaghoṣa's Saundarānanda, already mentioned above, is the easiest Buddhist mahākāvya. Śrī Harṣa's Nāgānanda is the best Buddhist play.
Since you live in a part of India where traditional Sanskrit learning is still strong, it would be a shame to only study on your own, though. Anyone who wants to read any kind of Sanskrit would benefit from studying the Laghusiddhāntakaumudī and a little Kālidāsa with a pandit (especially if they teach entirely in Sanskrit). If they're willing to read Buddhist texts with you, that can also be very interesting and helpful.