It's less the type of material, it's rather the dependence on RNG
Firstly, thanks to Dr. Kaii for bringing this up so that we can improve this game in a constructive manner!
Then, to your question: after 200+ hrs with The Engineers, after unlocking 12 of the 15 so far, and after trying to determine reliable sources of all the components (see this
doc from the team around Qohen Leth), let me summarize my opinion here:
1) Basically, all spawn mechanics rely on RNG. You can increase your odds significantly at times (right planet, right SC place, right system state), but it all boils down to winning in the RNG lottery. In some cases, the odds are really low, so that some CMDRs can do the right activity for hours (see surface mining example below), and are still not successful.
2) Some activities that can increase the odds are against the preferred gameplay of some CMDRs, like fighting in CZs, killing innocent traders, raiding surface bases, shooting barnacles. These CMDRs will feel excluded from key The Engineers features.
3) There are too many different materials/components. The maths is very simple: the more different materials there are, the less likely it is that the one you are searching for is spawning.
How can this be improved (which is basically the TL;DR
):
- reduce the number of different materials/components in game
- introduce some likelyhood, that even when focussing on only a few types of gameplay, you can still get all materials
- material mission rewards should follow the same rules as spawn mechanics, so we can improve the odds of finding the right missions by picking the right system
- reduce the reliance on specific USS/POI spawns
Here are some very personal examples of frustrating gameplay:
a) Surface prospecting = searching for Polonium: I had cases where even with 2 hours on a planet, I was out of luck. And yes, I searched specifically for metallic meteorites, and yes, I had found Polonium on this planet before, as confirmed in the community resources. Here's a little mathematical
emulation I did. This is based on many assumptions, but the numbers feel quite right to me. TL;DR: as the spawns are based on RNG (mostly), you still are facing significant odds of NOT finding Polonium within the first hour on a planet
b) USS scanning = searching for Pharmaceutical Isolators. They spawn in outbreak systems (which are very few in the first place!), in encoded emission signals. But USS only spawn every few minutes, and then only a few are encoded, and then they not only spawn debris, but also private data beacons and such, and then the spawns for Imperial or Federation rares (Imperial Shielding, Cor Dynamics Composites and such) overrule ... please do the maths for this case yourself
c) Mining for Painite: the last time, it took me 2.5 hours and 300 limpets to collect 10 tons of Painite for Selene Jean! Yes, I have done a lot of mining before, and this was a pristine metallic ring which has yielded a lot of Painite for me before, but the introduction of Praesodynium and Samarium has (by pure maths!) significantly decreased the odds of finding this one specific material. I'm not sure if this was intended by FDev
Happy to discuss with you or with FDev. I find it a bit unfortunate that this key feature was NOT part of the beta testing (remember the fish?)