Sri Ramakrishna Kathamritha is wonderful. It's good to read once.

It tells the teachings of all traditions.

Bhagavatam is wonderful; tells about many systems and leads to Bhakti.

Shata Sloki Ramayan in 100 verses tells the Ramayan.

Then Sri Ganapathy Sachidananda's discourse are full of wisdom.

Uttara Gita is like Bhagavad Gita, in more detail.

Bhakti is several methods. Nama Sankirtana, is one of best.

Nama Smarana is remembering.

Pranayama is wonderful, beyond so.

Meditation is even higher than japa, as per teachings.

But the energy of bhajans and japa are main path for creating the space for meditation.

Bhajans are of a few different types; i.e.,

1. A conversation between the devotee and God,

Or several others