The only improvement I need in Eclipse is it consumes a lot of RAM, which makes my PC slow. 

If the Eclipse team can solve this issue, it would be very impactful for us (Developers).

Also, opening a big project in Eclipse sometimes hangup the eclipse itself. If this issue gets fixed, it would be a big achievement, as I have been seeing this issue for a couple of years.

Eclipse can sometimes be a plugin nightmare. Various plugins require different versions of the same plugin running for different reasons.

Other than these issues, everything looks good.

The development of the product needs improvement.

I would expect the team to fix any existing bugs related to performance and make it more stable for future releases.

I would like to see it extend native support for functional languages like Scala.