What did Mizoram gain as a result of the peace agreement in 1986?

Full-fledged statehood with special powers

As per the accord, Mizoram was granted full-fledged statehood with special powers.

Mizoram was a Union Territory before the peace agreement, but it implies that Mizoram gained full-fledged statehood as a result of the accord. At the end of two decades of insurgency, everyone was a loser.
Laldenga came back from exile in Pakistan and started negotiations with the Indian government. Rajiv Gandhi steered these negotiations to a positive conclusion. In 1986 a peace agreement was signed between Rajiv Gandhi and Laldenga. As per this accord Mizoram was granted full-fledged statehood with special powers and the MNF agreed to give up the secessionist struggle. Laldenga took over as the Chief Minister. This accord proved a turning point in the history of Mizoram. Today, Mizoram is one of the most peaceful places in the region and has taken big strides in literacy and development.