I'm not an expert in wood conservation, but I reckon that a bit of wood nourishing oil and wax will be good for the longer-term preservation of the hilt.
Plus, being of a dark hue, you wouldn't need to worry that much about oil stains marring the wood, which can happen to expensive pelet wood with light colour tones.
Which brings me to my next point - I've seen people put kerises wet with oil into the sheath, and guess what happens --> the mouth of the sheath gets stained permanently, and if there is really a lot of oil, some of it can seep upwards into the hilt (especially if you have thread covering the whole pesi). And if you have a light-coloured wooden hilt or ivory, you can get ugly stains at the bottom of the hilt. Again, they will be permanent stains.
So bottomline is to be careful with the amount of oil used - more is not always better. Whatever oil (applied sparingly and evenly) the hilt or blade cannot absorb should be wiped off and the blade or wood looks moistened but "dry".
A bit on micro-crystalline wax - I spoke to a conservator once. He didn't explain but he seemed to be against the idea of using micro-crystalline wax on wood and ivory. Could be something to do with the fact that the wax gets embedded into the surface and is hard to remove. Maybe it stops him from administering further conservation treatments, and he has to remove them before doing so.