I guess I would ask if there are many posts that deserve merit that have little to no merit? If so, the number of sMerit that sources have should be evaluated or the number of sources should be evaluated. I don’t think adding a “plus 1” would add much value. In addition to the potential for abuse I mentioned above.
I'm pretty sure there is, that's why we see those Merit GA threads from time to time. Some get drowned among the repetitive replies, and then the local boards though since the exposure is lower.
About the +1, I feel it's more of a complementary feature. Think of it as a reaction. Let's say you post a thread on
Bitcoin Lightning Network Satosheeesh v69 (just for discussion sake) detailing its new features and how-to.
People visit your thread and get intrigued. Since the "Like" reaction is pretty much one-click and "free", they'd be more inclined to react positively. So perhaps like 6 hours later, you revisit it to see 35 likes and 7 Merits thrown in.
If the substance is good, it's pretty easy to distinguish it among the rest. Sure, we might see some sockpuppets liking their own posts but all it takes is just several seconds to scan and we can tell if they're BS or not.
Automating notifications to merit sources may also be a good idea as was suggested above by Welsh. Sources could set their own criteria as to who they are willing to receive notifications from.
Without setting up Telegram/ PM/ smart watches, notifications would likely be seen in the Epochtalk ʷᵉ ᵐⁱᵍʰᵗ ˢᵉᵉ ⁱᵗ, ʷᵉ ᵐⁱᵍʰᵗ ⁿᵒᵗ. ʰᵒᵖᵉᶠᵘˡˡʸ ᵇⁱᵗᶜᵒⁱⁿ ʷᵒᵘˡᵈ ˢᵗⁱˡˡ ᵇᵉ ʳᵉˡᵉᵛᵃⁿᵗ ᵇʸ ᵗʰᵉⁿ