If you install extensions as On Demand, applications which you are not using will not use computer resources.
You can install applications, and you can remove applications. So you can try various applications, then those you don't want to use can be removed. To remove applications, open Apps Audit. Click Dependencies -> Build Reporting Database. When that has finished, click Mark for Deletion. You need to reboot your computer for applications to be removed.
Different people have different preferences with apps. You should find that all, or most, applications should run on your computer. Until a couple of years ago, I was using 512 mb RAM.
I use:
Leafpad text editor
Xfe file manager
The latest version of Tiny Core has a file manager and text editor on the base, so you may use them.
Firefox
Open Office
Filezilla ftp
epdfview
With On Demand applications don't use computer resources unless you run them, so you could install both Opera and Firefox, for example.
Because you can remove applications, try a number of different applications for each purpose, and remove those you don't like.
With conventionally installed operating systems, adding and removing applications, particularly if done a lot, has the potential to corrupt the filesystem. With Tiny Core, adding and removing applications will not corrupt the filesystem.