As I'm waiting for my EU client to download the stuff I decided to post here our findings form PTS. Again great thanks to all those kind testers who helped creating this list.
I bolded milestones rewards and significant rewards. According to testers if you choose one costume on a leveled character you can still chose another one if you level another character, the same with pets, until you run out of choices.
Crown crates and other acoount shared rewards are once per account, so no, you can't level 5 characters in a row and get 5 crates everytime one hits level 20
For now the crates will NOT change with crate seasons change as per post in this thread:
https://forums.elderscrollsonline.com/en/discussion/399928/level-up-rewards
Level 3: Crown Fortifying Meal
Level :4 Trifling Glyph of Health (green), Choose one: Homespun breaches, Rawhide guards, Iron legs (all green)
Level 5: Two Green-quality Rings, part of a basic 2-piece Item Set that grants a Max Health bonus
Level 6: 3 Soul gems, 1 Crown Experience Scroll
Level 7: 500 gold, Bag Space Upgrade (apparently if you already bought some bag space upgrades on this char you do NOT get a free one)
Level 8: Choose one : Tailor’s Crafting Box / Leatherworker’s Satchel / Blacksmith’s Crafting Crate (the crafting containers
contain basic crafting mats of the selected type)
Level 9: Choose one : Prophet’s Inferno Staff / Greatsword / Shield / Bow /Restoration Staff / Dagger (green quality)
Level 10: Sorrel Horse (account wide)
Level 11: 25 Gold Coast Swift Survivor Elixir
Level 12: Crown Refreshing Drink
Level 13: Recipe: Tarragon Chicken, Poultry, Seasoning
Level 14: 10 Lockpick, 3 Counterfeit Pardon Edict
Level 15: A choice of 6 blue-quality weapons (Prophet’s Inferno Staff / Greatsword / Shield / Bow /Restoration Staff /
Dagger)
Level 16: Tailor’s Advanced Crafting Box / Leatherworker’s Advanced Satchel / Blacksmith’s Advanced Crafting Crate (the
crafting containers contain basic crafting mats of the selected type) (+ 1 bank upgrade if it's your very first one).
Level 17: Choose one : Slight Glyph of Hardening, Slight Glyph of Absorb Magicka, Slight Glyph of Weapon Damage (blue
quality)
Level 18: Storage Coffer: Fortified, Choose one (furniture green): Imperial Brazier, Spiked / Imperial Bed, Single / Imperial
Bookcase, Swirled.
The “Storage Coffer, Fortified” collectible can only be obtained from the Level Up Advisor at level 18.
Level 19: 2 Crown Repair Kit
Level 20: A costume of choice and a Fire Atronach Crown Crate Choose one: Lion Guard Knight / Covenant Scout / Mages Guild Formal Robe
Level 21: Choose one: 10 Embroidery / 10 dwarven oil / 10 Turpen
Level 22: 25 Crown Tri Restoration potion
Level 23: 3 Porade, 3 Jejota, Makko, Deni
Level 24: Choose one (cosmetic pet): Alik’r Dune-Hound, Abecean Ratter Cat Level 25: A choice of 6 purple-quality weapons (Prophet’s Maul / Bow / Lightening Staff / Shield / Restoration Staff / Axe)
Level 26: Minor Glyph of Shielding (purple)
Level 27: Chose one: Treasure Map I ( Glenumbra / Stormhaven / Auridon / Grathwood / Stonefalls / Deshaan)
Level 28: Choose one : Tailor’s Expert Crafting Box / Leatherworker’s Expert Satchel / Blacksmith’s Expert Crafting Crate
Level 29: Choose one: Crown Lesson Riding : Speed / Stamina / Capacity
Level 30: 4,000 gold and a Fire Atronach Crown Crate
Level 31 Choose ten Woodworking mats - either Maple, Oak or Beech .
Level 32 Choose 1 of 3 Dye Stamps. Holiday: Ivy-Berry Blend - Oblivious: Cheerful Cliff Racer - Darkening: Dark of the Moons.
Level 33 Choose one Chest Armour Piece from Heavy, Medium or Light. Blue, one piece set.
Level 34 Choose one: 80 Crown Lethal Poison, 80 Gold Coast Trapping Poison, 80 Gold Coast Draining Poison
Level 35: A choice of 10 purple-quality crafting-improvement materials - for one of the 3 equipment craft.
Level 36 Cyrodiil Assault crate - 10 Siege Repair, 2 Fire Pot Trebs, 2 Rams.
Level 37 Three purple Crown Fortifying meals
Level 38 Choose a Crafting Mats Crate for either cloth, leather, metal, or wood. Contains 10 of the level 36-44 mats plus one style mat.
Level 39 Instant All Research Scroll. Shortens all on-going research by one day.
Level 40: 6,000 gold, "Ragged Style Box" containing the Prisoner's Rags Outfit Style - apparently it's not a crafting motif, Also 1 Outfit Change Token.
Level 41 Choose one weapon - same range as before but blue quality, one piece set.
Level 42 Choose either 25 Spell caster's Elixir or 25 Warrior's Elixir.
Level 43 One Attribute Respec Scroll and one Skill Respec Scroll.
Level 44 Cyrodiil Defence crate - 10 Wall repair, 10 door repair, 2 Fire Ballistas, 2 Oil.
Level 45: An Undaunted Key So, when you do your Undaunted invitation quest you end up with 2 keys.
Level 46 5 Mimic Stones. Choose 20 level 46-50 crafting mats for either cloth, leather, metal or wood.
Level 47 50 Transmute Crystals. Choose one blue ring, one piece set, either Healthy, Arcane or Robust.
Level 48 Choose a pair of Purple Jewellery Glyphs from either 2 Stam Recovery, 2 Mag Recovery, 2 Phyisical Harm, or 2 Magical Harm Glyphs.
Level 49 One Crown Experience scroll.
Level 50: 10,000 gold and a Fire Atronach Crown Crate
All this information is based on PTS testing, if anything doesn't mach live let me know asap. Thx
and have fun leveling.