Consider changing imports

According to [Material-ui](https://material-ui.com/guides/minimizing-bundle-size/), bundle size might depend on the way we import stuff.
```Typescript
import { Button, TextField } from '@material-ui/core';
```
OR
```Typescript
// 🚀 Fast
import Button from '@material-ui/core/Button';
import TextField from '@material-ui/core/TextField';
```
This needs investigation and discussion.