That's a lot of eggplants on each plant. You must be doing something right :-) Agree with farmerdilla. If I let one old fruit go to seeds, the plant seem to stop bearing new fruit. I wouldn't know the limit because I never had one plant bearing so many fruits like yours (I ate them when they come along). But they may stop setting new fruits anyways when weather gets too hot or too cold then harvesting will not help new fruit.

The emergent leaves of 'Barmsteadt' are covered with whitish indumentum. Rub this off and the leaf surface beneath is light green. Indumentum is a characteristic inherited from species ancestors, especially yakushimanum, but also pseudochrysanthum, pachysanthum and others. Brown or reddish brown indumentum comes from bureavii, taliense and others. The color of 'Redwood' leaves comes from rhododendron insigne. Rhododendron hanceanum has chocolate brown new leaves. For many years, hybridizers concentrated almost exclusively on blossom size and color. In more recent times, attractive and unusual leaves have become more of a priority.

Samantha 'Dusty' makes me think 'water retaining'. I see just a bit of perlite in photo, and it looks yellowish/discolored to me: this happens with too much water. So it was likely watered/kept wet in the past. Maybe it is time to repot. I keep mine in gritty mix made of grit+sifted perlite (to get rid of dust and smallest particles) and smaller amount of turface. Pumice, if you have it, is good to use instead of perlite. Some ppl use mix of Cactus&Succulent soil and perlite, in 50/50 or 40/60% ratio. Either would give good drainage. If plant is in warm environment, it could be watered more often, thoroughly rather than in sips. To stop mix falling/washed out of container, a piece of bug screening is of great help. Or any mesh with smaller holes, drywall tape is good too. Or plastic canvass sold in crafting store like Michaels. If there is lots of peat in your mix, it could become hydrophobic if let to dry out completely, and very difficult to re-wet. So roots will not be getting any water, it will just 'slide' over the soil and make you think it drains well. Scarring on the leaf could be mechanical damage that healed over, either from something falling/brushing against the leaf or chewing by bug or pest. It's hard to tell, but I do not think it has anything to do with light. Those small marks are bit peculiar to me too as palms pointed out. Are they on any other leaves or just that one? Your lighting sounds OK. I do not really know LED grow lights as I do not use them. I keep succulents under light thru the winter, and outdoors as soon as weather is suitable. They are in full, direct sun (I consider 'direct' what is outdoors, not filtered thru the windows - but that's just me :).

The pot is placed a few meters from direct sunlight ==>>> its indoors.. it gets NO direct light ... mostly because there is a window in the way ... and its simply too far from the diffuse light from that window ... the third pic seems to show very good new growth ... why do you say its brown?? ... how about a closer pic ... its going through some stress from moving it from one place to another ... all plants shed older leaves ... annually.. it can be increased due to stresses like moving it ... i think you are on the verge of loving it to death ... try to chill a bit.. and settle in.. and try to get it closer to a window... there is a houseplant forum ... where you can learn all about such ... ken