I’m currently coding a game from scratch, and I’m currently planning to write a very basic 2d graphics engine using LWJGL first so I can make sure the engine and netcode function properly. I’m not very familiar with jMonkeyEngine, however, and I don’t know what it offers in terms of pregenerated code, or if it requires using the IDE, or anything else that might come up. Is it simple to integrate jMonkeyEngine for rendering after all is said and done, or would it be better to start over and build the game from the ground up taking jMonkeyEngine into consideration?
I can only suggest to run through some of the examples and see what JME can offer: scene graph, physics, networking, GUI, terrain, particles, and advanced shader pipeline. JME provides a lot of optimized functionality for you, so it is worth taking a look at if it fits your criteria.
You do not have to use the JME SDK (netbeans IDE), you can use Eclipse, but the SDK provides a lot of nice tools (and you can 1-click configure it to have the same key map as Eclipse if that is the concern).