Yes, I agree. Artificer is an even better one level dip at character level 1 for a spellcaster to pick up Concentration saving throw proficiency and shield proficiency, if you don't care about Fighting Style, and don't need heavy armor proficiency.
Regarding spell components, honestly, it is an annoyingly complicated rule that should not be needed any more in my opinion. I put together a summary for A5E for which cases you don't need a free hand. See this ENWorld thread:
Level Up (A5E) - Do material spell components always require a free hand in A5E?
If you're wielding a weapon, you can sheathe and unsheathe it to get around the free-hand requirement. Likewise, with a two-handed weapon, you can temporarily hold it in one hand while spellcasting.
The only way to avoid this is to make a house rule: "A free object interaction is used when casting a spell with Somatic or Material components. You cannot (un)sheathe a weapon or drop then pick it up as a free object interaction on the same turn."
But honestly, does it make spellcasters significantly more powerful if you allow them to wield a weapon and/or shield while spellcasting? No. The benefit is pretty minimal, coming down to whether you have a weapon in hand to make an opportunity attack when someone moves outside your range or similar.
So I would be more than happy to house rule that we don't care about a free hand when spellcasting. You do the weapon shuffle, or your shield is strapped to your arm, and I don't want to track in a fine-grained manner whether your weapon is sheathed or unsheathed.
Anyway, ignoring the whole issue of spell V,S,M components, the Shielded Caster feat I proposed would still be worthwhile. In simpler terms, it is the following:
Shielded Caster
General Feat (Prerequisites: Level 4+; Spellcasting or Pact Magic Feature)
- Shield proficiency
- Constitution saving throw proficiency
- You can use your shield as a spellcasting focus.
And if there's a Sorcerer grumbling about already having Constitution saving throw proficiency, then I'd give them a +1 ability score increase instead.