The reason for removing legacy support was the growing complexity of the code required in order to maintain it, and thereby support it.
When I released it to support v2.0 I tried to be open about the fact that legacy wouldn't be maintained indefinitely and with v2.0.2 I put a notice that v2.0.3 would finally remove the support as I didn't want anyone with any nasty surprises.
We have to strike a balance between creating a plugin I can maintain while we work on bigger projects might earn us a living.
I'm sorry this has caused you inconvenience, but if I was to be able to maintain the plugin going forward, it had to be done.
Except for the CSS compiler in v2.0.3, there's currently not a huge difference between that and v126.96.36.199. So for now, you're not missing out too much.
As for alternative, no, I haven't seen another plugin that offers this functionality on WordPress.org for free.
I hope this helps to explain our position better.