It should be pointed out that it's possible for the seller to overcharge for Simple Delivery, but there is no motive to do so because the seller won't receive any of the charge and it just makes the total price less attractive to buyers. I see, from general browsing, plenty of items which are clearly in too high a SD price band, presumably put there by eBay's AI and not corrected by the seller. Does eBay think it's valid to penalise sellers for not correcting eBay's mistakes when the sellers are already being penalised by having their items more expensive for no gain? There's also the matter of whether the SD prices are reasonable, or perceived as such (obviously outside the seller's control but the buyer may not realise, or even realise they are 'scoring' the seller rather than eBay). That's the logical bit covered, but of course if people are (wrongly) given the option to mark you down some will do so even though they have no justification at all.
So, yes, of course it should be automatic 5 stars when using SD (eBay do want to encourage you to use it, after all), and they might even agree if it were easier for people to contact them and suggest it.
