try icewm or, simple use openbox, and if you need panel some tiny panel... For me all old image(3.14) with openbox, removed pulseaudio and mali(less thant 100mb ram usage after start) - stable and have greate perfomance in all "desktop" scenarios. In you case, with 1gb i strongly recomend use armhf browser instead of arm64 if you need havy browser like chromium or firefox. And very important - disable all kind of hw acceleration in browser setting...