Comments on individual topics--
Charisma vs Intelligence Skills
Charisma and intelligence skills are both campaign-gate skills, but there are likely difference in how they play out in campaigns. If you miss a Persuasion skill check, perhaps you do not make a friend or convince someone to help you. If you miss a History check, the party might not know that the solution to their problem is kept at castle Anthrax. This seems like it makes the Intelligence skills more powerful, but it might not play out that way. DMs often want the party to find the adventure hook, so if no one in the party is good at the requisite skill, sometimes the hook finds other ways of getting to them (perhaps the potential friend the Persuasion check will gate knows this).
Constitution vs Wisdom Saves
The mind is greater than the body... Says no construction worker ever!
If you'd asked my thoughts on this back in early 2014 I'd have said Constitution for sure. They help concentration saves and they still often carry some fairly rough effects often along with high damage. Contrary to popular belief, damage does matter quite a bit to Tier 1 and Early Tier 2 Wizards and Sorcerers.
That said, a level 1 healing word can solve the 0 hp condition. It's a bit harder to stop a hold person or similar. As such I think that while the Constitution saves that Sorcerers have proficiency in come up a bit more often, that the effects wisdom saves prevent are more often worse.
Which Wins When
IMO. When it comes to Constitution or Wisdom saves It's a tie, though if forced i'd give wisdom an ever so slight edge. One of the worst TPK's we ever had was our Paladin was dominated and forced to smite the rest of us to death.
Saving throw proficiency is kinda mixed in that it depends on campaign, but also what else you are going to do with your characters.
- Constitution saves gate concentration saves. These matters variably depending on how you play your casters (how up front you are, how much you rely on concentration spells, etc.). They also are often so important that people select feats (War Caster, Resilient) to enhance them. An advantage for Wizards is that a wizard is more likely to want to select Resilient: Constitution (getting also a +1 to Con) than a Sorcerer is to get Resilient: Wisdom (this is still likely level 12+, at least if you do array/point buy).
- Wisdom saves gate some low-level shutdown spells like Command and Hold Person (making starting out with a strong save there important), but also Dominate and many monster abilities. Generally there is more shutdown among the Wisdom-save effects, and more Debuffs among the Constitution-save effects, making wisdom slightly more important. However, there are non-save-enhancement answers to the Wisdom ones, with spells and ancestry/class abilities which provide immunity to whole categories of the effects (charms, paralysis, etc.).
Origins
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Sorcerer Top 3
- Entertainer (Musician) (Cha, Dex)
- Wayfarer (Lucky) (Cha, Dex)
- Acolyte (Magic Initiate Cleric) (Cha)
Wizard Top 3
- Sage (Magic Initiate Wizard) (Int, Con)
- Criminal (Alert) (Int, Dex, Con)
- Acolyte (Magic Initiate Cleric) (Int)
I'd suggest Entertainer and Sage are the respective best Origins, though there's a strong case for the others as well. Having an extra spell and cast in tier 1 feels really good. So does being able to hand PB of your allies Heroic Inspiration once every short rest.
Which Wins When
I had came into this thinking Wizard with Sage would have a slight advantage. However, on careful consideration I'd actually give this to the Entertainer Sorcerer. Heroic Inspiration can be more front loaded into combats and just as impactful as any first level spell. That it comes back on a short rest also makes it excellent for skill check buffing. I think Sage's Magic Initiate can make a case for level 1 or 2 when spell slots and spells known are generally really low and it's skills are generally more useful. Maybe if it was Magic Initiate Cleric or Druid, that Sage granted, but Magic Initiate Wizard just isn't enough.
I've found approximately equal use for Alert, Lucky, and Musician -- going first (sharable), inspiration (sharable, per short rest), and advantage (saves, PB/day) are all huge effects. Magic initiate I think are best when they open up new spell options (so yes, sage is not best for wizard).
Skill and tool/kit proficiency are a harder nut to crack. Sometimes it is best to play into your strengths, other time to fill in gaps for your party. The one that stands out to me is Wayfarer in that it grants Thieves Tool proficiency, but not access to Arcana (for disarming magic traps) or Sleight of Hand (regular traps, and locks). I've always wondered why this was included on a background that didn't also get the Skilled feat, as it makes its usefulness contingent on getting those skills some other way. The sorcerer gets Arcana, but not SoH, making the tool proficiency kinda limited in use. All the rest, it's really group dependent.
Spell List and Known/Prepared
Wizards continue to have more spells available that Sorcerers do not than the converse. Several of them (just in levels 0-3:
Toll the Dead, Find Familiar, Identify, Tasha's Hideous Laughter, Rope Trick, Animate Dead, Leodmund's Tiny Hut, Summon Fey, and
Summon Undead) on a lot of often-taken lists. A few more or fewer spells chosen is not make or break, but not having access to the thing you wanted to do at all can really change which class you will want to take.