EzekielRaiden
Follower of the Way
Though I don't run 5e myself, I know the rules well enough to comment, and my GM philosophy doesn't change between this and the game I do run (Dungeon World). As a general rule, I try to be favorable to players when I can, though I also let them know that if they convince me something is reasonable, it is possible their enemies can use it against them, too, should such a situation arise. That isn't common, but it has happened.
For object use, it's...pretty straightforward. Does it have hands? Paws are pretty bad for throwing things, they're usually for standing on. A creature like a raccoon, for example, genuinely has hand-like front paws. A flying creature could probably hold some small objects in its regular feet (birds tend to have highly developed grasping talons for a reason!), but "throwing" is pretty much not a thing--dropping, definitely, but not throwing.
For wands and other magical items, I'd treat the familiar as an extension of the caster in many cases--but this would be a big loophole for their opponents to use familiars for similar purposes, so they might think twice about advocating for a world where familiars can use wands to cast spells. As a control on familiars using such things, if we're treating the familiar as an extension of the caster, that applies to attunement in both directions. Either the caster can't have their familiar attune to things that require being a spellcaster....or they can, but it eats up the caster's own attunement slots because the familiar is "piggybacking" on the spellcaster's power. Both of those seem reasonable to me, and I'd accept whichever of them the player(s) collectively prefer--but we'll pick just one and stick to it for that campaign.
For more out-there stuff...I mean if the rules don't tell us, we talk it out. Generally, I prefer to favor RAW unless it is so blatantly, unavoidably stupid that it cannot be justified without brain-melting mental gymnastics, but when RAW is silent, we talk things out.
For object use, it's...pretty straightforward. Does it have hands? Paws are pretty bad for throwing things, they're usually for standing on. A creature like a raccoon, for example, genuinely has hand-like front paws. A flying creature could probably hold some small objects in its regular feet (birds tend to have highly developed grasping talons for a reason!), but "throwing" is pretty much not a thing--dropping, definitely, but not throwing.
For wands and other magical items, I'd treat the familiar as an extension of the caster in many cases--but this would be a big loophole for their opponents to use familiars for similar purposes, so they might think twice about advocating for a world where familiars can use wands to cast spells. As a control on familiars using such things, if we're treating the familiar as an extension of the caster, that applies to attunement in both directions. Either the caster can't have their familiar attune to things that require being a spellcaster....or they can, but it eats up the caster's own attunement slots because the familiar is "piggybacking" on the spellcaster's power. Both of those seem reasonable to me, and I'd accept whichever of them the player(s) collectively prefer--but we'll pick just one and stick to it for that campaign.
For more out-there stuff...I mean if the rules don't tell us, we talk it out. Generally, I prefer to favor RAW unless it is so blatantly, unavoidably stupid that it cannot be justified without brain-melting mental gymnastics, but when RAW is silent, we talk things out.