I'm running my first ever campaign. The party of 4 are trying to unite a valley community (a kobold tribe, a human village, and a dwarven expedition) together against the incoming orc invasion. If they ever succeed, I wanted to gift them some magic items from the communities.
To the warrior, a gift from the dwarves: A really big, high quality two-handed sword with the reach property. If it kills a creature, it also does 1d6 damage to another enemy within 10 feet of the wielder that is adjacent to the killed creature.
To the dragonborn Paladin, a gift from the kobolds: A shield made from eggshells that were broken by the orcs. (The idea is that kobold eggs are really hard at first, and they become softer and softer toward the end to let the kobold get out.) The shield provides an additional +1 AC (for a total of +3) when the wielder is under half HP. When the wielder would take physical damage (bludgeoning, piercing, or slashing), reduce the damage by 1.
To the fat Halfling Life Cleric: a magic mace. When you heal a creature, the mace becomes a +1 weapon until the end of the wielder's next turn.
To the Mage: an amulet from the alchemist's daughter. Once per day, you can cast a spell as if it were one level higher than the slot used to cast the spell.
Items do not require attunement for the character they are gifted to. If another character wants to use it, it needs attunement.
I want to give them "permanent" items, something they'll keep from this adventure. Not a 3 charge item they will discard after 2 sessions.
Are those items too strong for low-level characters? Is one stronger compared to the others?