Would these adjustments to the ranger archetype Beast Master help the animal companion be more useful?

I recently playtested a Beast Master ranger from level 1 to level 20 (I was playtesting a new homebrew archetype, which was my primary reason for doing so; the Beast Master ranger was just one of the other party members), but there were a few things I noticed regarding the relative power of the beast companion itself. For reference, the beast I went with was a wolf, which is probably a fairly standard choice.

Issues

Now, I know that Beast Master rangers are infamously weak, but I still wanted to see if I could try to improve what I felt were some of its weakest points during my playtesting. I was already using the popular houserule of letting the ranger tell the beast to attack using a bonus action instead of an action, but the other things that bothered me were:

  • Relatively low HP (as the first linked Q&A points out), although this was more of a problem during Tier 1/2, less so during Tier 3/4, at least during my playtesting;
  • Hardly any hit die, which is related to the above problem, since I remember having to spend a lot of healing resources to keep bringing the wolf’s health back up to full/close to full;
  • The DC for resisting the knocked prone secondary effect from the wolf’s Bite attack remains pathetically low at DC 11 for the whole game.
  • The lack of any saving throw proficiencies really screwed the wolf over during the big finale where it died to a meteor swarm, but with a decent DEX saving throw bonus, it would probably have made it.
  • I was sometimes hesitant to use the wolf, because it was dropped to 0 HP a few times at lower levels, unless I knew it would probably land the killing blow or could avoid an opportunity attack or otherwise being hit.

I will point out that at higher levels, the AC was fairly decent (for a wolf), and the HP wasn’t as bad as it was at earlier levels, and I was impressed with the damage output thanks to attack rolls and damage scaling with the ranger’s proficiency bonus. Its Stealth and Perception skill bonuses were also impressive. These things I don’t feel the need to change.

Changes

Here are the changes I propose, somewhat inspired by the UA Sidekick rules:

  • You get a new hit die whenever you take another level in ranger, so at level 3 your wolf starts off with two hit die, but at level 4 they would have three hit die … by level 20 they have 19 hit die. I doubt this would make their max HP better than four times the ranger level, so it would only really be for the purposes of short resting.

  • To improve the max HP a little, maybe something as simple as adding the beast’s CON modifier to that, so it’s now:

    \begin{align} \text{ (ranger level + beasts’s CON modifier)} \times 4 \end{align}

    This way, the animal’s toughness is also taken into an account; I feel like the wolf having 5 instead of 4 more HP each level would have been just enough to help, combined with more hie die to heal, but also from a flavour perspective, I feel like choosing a boar should end up tougher than a hawk, whereas RAW, they would both have the same HP. I would however, keep the minimum HP gained per level to 4, in case the beast somehow has a negative CON modifier, since I think taking HP away from the beast would be cruel, given how underpowered this whole archetype is.

  • Any DCs it has, such as the wolf’s ability to knock people prone, should scale with your proficiency bonus, like this AC and attack/damage rolls do, so rather than a measly 11, at level 3-4 it would be 13, and at level 5, it would be 14 … ending up at 18 at level 17+.

  • Unless it already has a "physical" saving throw proficiency (meaning STR, DEX or CON), it gains one of your choice at level 3, which of course would just mean a +2 (because that’s every valid animal companions’s proficiency bonus) but that also has your proficiency bonus added to it, like AC, etc. This would have certainly helped when it was hit by meteor swarm during our final level 20 showdown, it might have actually survived (even with its RAW hit points) had it made that DEX saving throw.

  • Finally, since I’m letting the beast be commanded as a bonus action, the first half of the 7th level ranger feature Exceptional Training is kinda wasted, so I was considering changing that to not only make the beast’s attacks magical, but also to effectively give the beast a rogue’s Cunning Action, which it can use if you command it to using the same bonus action you used to command it to attack (or do something else with its action). In short, you use one bonus action to tell it what to do with its turn, and it can now effectively use its action and bonus action to do something useful.

Question

Do the above changes seem reasonable, and do you foresee any balance issues coming from my proposed changes? My intention is for the Beast Master’s beast in particular to become more useful and survivable, without increasing its damage output (since I was happy with that), but not making it more powerful than I intended by overlooking something. I suppose also double checking whether there’s a problem with making some animals tougher than others based on their CON; does this unfairly favour tougher animals to the point where that’s a balance issue in and of itself?