Which approach to building an application should you choose?

Question

PHP

There was a dispute in our team about how best to build a web application. Help to decide, to find the arguments "for" and "against".
Application
Admin panel for a limited number of users. The panel presents data in graphical, tabular and text formats. It is possible to upload data in the form of csv / pdf / or other formats. Clients are just browsers. Working with search engines - not interested. Important aspects of security, simplicity and speed of development.
Approach 1. Standard MVC.
Authorization through sessions, pages (markup) is generated by views on the server. Pros: less load due to authorization (the second approach will lead to the fact that for each request it will be necessary to repeat the full or simplified authorization procedure), it fully fits into the framework paradigm.
Approach 2. Independent JS client + REST service
The js client is fully responsible for the markup, processing the json data coming from the server. The server receives hash-signed requests and responds to them with json. Pros: we completely separate the client from the north, we refuse sessions, it is more convenient to work with json with large amounts of data (with the first approach, you will probably have to make separate views for ajax downloads.

Answer 1

Anyone who is comfortable. But the standard MVC on the web is impossible (what you called it is not it) :)
In the second case, it will be possible to separate the development of Front and Backend, that is, there will be a slight overhead for interaction, but the development processes of both parts can be almost parallel, that is, there will be acceleration of development in general.