@Niara

Spell Preparing You're equating "more restrictive" with "worse," which isn't necessarily true. Restrictions, after all, are required to make a game good (cough cough racial ASIs :P). Having to prepare spells in specific slots both limits caster power and makes prepping spells each day more tactical. I don't think we should go fully back to that system, but a middle ground isn't necessarily worse.

Bard I agree with most of your specific things, especially abjuration, spells involving inspiration or words-- Aid, Curse, Speak with Dead, etc--and utility spells. Why do you think Bards should have access to necromancy spells? Just for the general "I want to be able to play that character type" or is there a specific necromancy bard trope?

Save DCs and Exhaustion: +14 to hit: 5 from ability score, 6 from proficiency, and 3 from magical weapon. Against a 19 AC creature, you'll hit 80% of the time.
19 Spell DC: 8 + [5 from ability score] + [6 from proficiency]. Hmm so in your experience, spellcasters don't get often get the "+3 to spell DCs" magic items? (honest question; I haven't played many high level campaigns)

But it does seem like enemies in 5e are expected to fail their STs ~50-60% of the time whereas you're expected to hit ~75% of the time (base 65-70% plus it's easier to get advantage on attacks than impose disadvantage on enemy STs), so a flat penalty to STs results in a more significant drop in effectiveness. 50%->25% is half as often. 75%->50% is 2/3 as often.

Help I, at the very least agree, that you should be allow to Help with certain checks even without proficiency. E.g., Athletics or Perception.
As to your "guessing a DM's mind incorrectly," I'll argue only bad DMs wouldn't allow a player to change their Help action if it turned out that a different check is required. "Hey DM, wouldn't my character have known that Check B was actually required? I intended to help [do this task] which is still being done; can't my Help action still apply?" Also, in your games do players often use the Help action for uncertain ability checks in combat?? I can't recall a time where someone used the Help Action to aid someone's ability check in combat...maybe only ever to help escape a grapple? But in that case they'd more likely just Shove the grappler. I suppose with the new Search+ Actions in OneD&D this will come up more often..?

Partially I'm coming from a place of not really liking 5e's trivial Help Advantage. I'd prefer numerical bonuses (so that you can still benefit from other sources of Advantage) and that the helper has to make some type of check to actually provide a benefit.

Originally Posted by Niara
Having to stop dead mid turn because you have to use a different movement speed is dumb as balls.
Agreed

I've seen some of his videos. He does indeed move 30 feet and shoot two arrows in 6 seconds. Though I can still cling to my "against a stationary target" and "not in a stressfull/dangerous combat situation" defense; doing this in a real fight and accurately hitting would take more effort & time. :P