Can't talk for Linux, I am now using Eclipse on Mac.
I used Eclipse on Linux about 8 years ago, and I remember running into frequent issues at that time: the problem was that I was using Ubuntu 16.04, but the SWT widget toolkit maintainers for Linux were Red Hat employees and they were focused mostly on Fedora. For several months SWT was very unstable because the native nature of SWT made it difficult to support it on the different Linux distributions, especially during the transition from GTK2 to GTK3, and considering that Ubuntu was tweaking GTK a lot to achieve its own unique visual style. You can get an idea of the problems the Linux maintainers were having here [1]
At the same time, the release notes of Eclipse clearly stated that that particular version of Ubuntu was not supported. So maybe you are running into the same issue, maybe you are using a Linux distribution that is not amongst the list of officially supported (=tested) Linux distributions.
With respect to market place and plug-ins my experience is different from yours, but having worked on Eclipse plug-ins for years I am certainly a more expert user. As I already said, to me the worst aspect of Eclipse is the p2 package format. It probably solves many problems (e.g. it tries to guarantee that you don't end up with a broken Eclipse instance due to lack of dependencies), but I often think that they could have achieved the same by using plain-old Maven dependencies and BOMs.
[1] https://bugs.eclipse.org/bugs/show_bug.cgi?id=492371
Edit: fixed typos