Yes, it is fair to say the MOLA shader is 'old'. As to whether it will be improved, I think in general we are looking to the general-purpose Geog Heightfield and Image Map shaders for any future georeferenced heightfield data import. Geog Heightfield already supports MOLA data, though few people seem to realize this. In fact the GIS format back-end we use for the Geog shader nodes is pretty flexible and supports many formats including moon data (LOLA), and most commonly available Earth DEM data, e.g. from the USGS.
Loading MOLA data with the Geog Heightfield nodes is not quite as "one-click" simple as the MOLA Shader, but it's a lot more flexible, powerful, and responsive in the end. To a single MOLA tile, you just add a Heightfield Load (DEM) from the Add Terrain button on the Terrain Layout, then navigate to where your MOLA data is and select the .lbl file (*not* the .img) for the tile you want to load.
If you want to load a complete set of given MOLA data, you just use the Heightfield (Load Multiple DEMs) option and scan the folder for the data you want to load (or manually add each .lbl file). It will take a while to individually load each tile but, unlike the older MOLA shader you'll get a clear progress dialog for each DEM that loads, and when it's all done you'll have individual control of every DEM that's loaded. Perhaps more importantly (for e.g. memory use), since georeferencing is supported, you can easily load a *subset* of the total data, using less resources, and still get the correct positioning, tile alignment, etc.
Having said all that, I only did some basic testing on the MOLA dat with the Geog Heightfield loader. It's possible there are some issues with it because it's mapping to a Mars-size planet (which reminds me: make sure you change your planet size to Mars-equivalent for accurate results!). Let us know if you do see any problems with the above workflow.