Unique coupon codes - I’m assuming that the reason you’re looking for unique codes, is that each coupon applies to only one person? If so, then with my app, you won’t even need unique codes, because the discount applies automatically to specific customers you select.
Specific products or collections - Regios Automatic Discounts supports limiting discounts to specific products, collections, or even variants.
Buy 5 items get Discount 10%, Buy 10 items get Discount 15% - it sounds like what you’re looking for are quantity breaks, where you can apply a different discount amount depending on how many items your customer purchased. If so, then you can achieve this using my app’s “volume discount” feature.
Amount transaction minimum - Regios Automatic Discounts supports adding a minimum order subtotal, or minimum quantity.
If you have any questions, reply in this thread, and I’ll be happy to answer.