Dire template for 5e

In D&D 5e there is a clear lack of templates compared to 3.5 where one could make anything from a pseudonatural cat to an advanced mighty dire half-fiendish tarrasque. Consequently, herein I try and reverse engineer the dire template.

The term dire seems to have been dropped on many creatures and replaced with giant, so a dire rat is now a giant rat.
The giant variants are rather arbitrary and change conceptually as opposed to based on a template.

Giant owl goes up three size categories, gains +10 strength and +6 intelligence, but only +2 HD and no speed increase. It kind of makes sense.Here is a link to the PF dire template. In 5e MM, the only dire creature is a dire wolf, which makes reverse engineering easy:

• CR    +2 (1/4 to 1)
• Speed +10
• hp: 2d8+2 to 5d10+10 —+3 HD and the HD go up a category.
• Size    +1
  AC    +1 —not +5 natural armour, which makes sense in light of the AC+proficiency changes
• Str     +5 —not +8
• Dex    +0 —not +2
• Con    +3 —not +8
• The mental stats are unchanged. Except for Cha +1 which may be a typo.
• +4 to +5 to hit (+2 proficiency, switch from finesse to strength, no focus). damage dice increase.

The increases are more modest, which could be a reflection on the game or simply the single sample.