Human Familiars only need to have the same element as their witch since they aren't born with their own like other magical creatures. Now if you want to be a Nature Sprite familiar then you can have differing elements like fire, plant, etc. (anything that would be in nature and makes some sense). You can be very creative with what species you're familiar will be as long they are somewhat humanoid but they can shapeshift all they want. For example a clockwork familiar with an electric element would be fine.
As for Hunters, yes they will be in possession of magical weapons. There are three branches of weapons they can choose. First would be:
Cursed Artifact - This mainly focuses on dark but highly effective magic that is best suited for combat. They are the most powerful out of all the weapons but come with a price. Like witches, these also have their own contract that binds their user to them. It can be as strange as one prick of blood each day to a pint of blood for each use. Be aware that the more dangerous the contract is the more powerful the artifact.
Holy Relic - Calls upon light magic to heal and grants its user the ability of fast regeneration. Those who possess such weapons are known to be hard targets to kill as they are able to heal injuries that have not be afflicted towards critical areas of the body (heart, brain, lungs, kidney, stomach, liver, etc.). There is also an increase in physical attributes such as superhuman strength or incredible eyesight. The only vulnerability of the relic is ironically itself. In order to properly wield such a weapon one must bind their own core or life energy to the object. If the weapon were to break (which is a rarity) the damage towards the users core may be irreversible as well as deadly.
Charmed Weapons - The most commonly used but weakest form of defence/offence. These are less dangerous to wield than its other two counterparts and have a more wide range of variety as well as uses. New recruits are usually in possession of these magically imbued weapons. Their powers come from the magical symbols of witches and the most common would only hold one or two inscribed onto its surface. The more symbols it has the more powerful it will be. The only way to gain more is to kill a witch and 'steal' theirs. Eventually they will be able to even rival Cursed Artifacts and Holy Relics.
(literally made these up on the spot so if anything doesn't seem right, tell me ^^)
Hunters can also be ex-familiars but their witch has to be deceased.
