With the clarification that we need both of the Stats in a related skill to be at least within 5 levels, I was looking at the two leading plans.
Plan "This train has no brakes v4" is very, very aggressive and is going to have long-term consequences of us almost constantly risking running into the Stat wall- and probably crashing into it.
Allow me to explain:
Under "This train has no brakes v4", the expected DADA is going to be 10 9 (it is at 6 right now, with 2 from training and the +1 from Ravenclaw that is 10 9).
But, we are currently at CRT/INT at 4. For us to not lose the +1 Ravenclaw bonus, we would need to increase BOTH CRT and INT. Now, the plan has both training...which is an approx. 36% chance of both succeeding. Well, this turn, if that fails, we have a pretty good probability of a level up...at which point we MUST put 1 point into CRT and/or INT. This cycle, we are within the stat line. However, the bonus comes every 5 months in during the school year.
But...what about the next +1 Ravenclaw bonus at the end of the year? To get that, we need to have another level up or spend lots of actions (or be luckier than we have been) to get CRT and INT to 6 5. Not too bad...so far. It really starts to come to a head in year 4 year 5 and gets worse in year 6.
From the start middle of year 4 year 5, we would have to get a +1 Stat to each of: CRT, INT, CON, EMP every 5 months from then on or else we would hit the Stat wall. Now, in year 4 and start of year 5, we might get away with actions to increase CON and EMP...but by middle of year 5 6, we would probably need 2 level ups per 5 months in order to keep up. Note that it gets harder to level up every time we level up.
But, that is excluding the skill requirements once we reach level 12 in DADA in mid-point end of year 4. Before the end of year 4 middle of year 5, we need to have 4 other skills at level 12 in addition to increasing the 4 stats by +1.
In year 5 6, we would need an additional 3 skills at level 12 and approx. 4 3 level ups or very good luck. This is, of course, not counting any spells we want to learn, potions we want to brew, or Alchemy we want to build.
Unless we want to agree that we will give up the +1 benefit from Ravenclaw in DADA...a less aggressive plan would be advised.
Edit: Changed from start of year 4 to mid of year 4 for having to increase EMP and CON.
Edit 2: Changed to 3 level ups in year 5.
Edit 3: Pointed out we will be Potions 9 under plan. Changed in order to reflect corrected estimations.