Frostmourne - Patch 3.3 should last longer than 3.2

Since its inception, Frostmourne was planned to have 4 phases, each of them with PVE/PVP content corresponding to WotLK patches 3.0, 3.1, 3.2, 3.3. The phases are supposed to last 3 months each, meaning that new content is to be released at an equal pace.

However, this may not be inline with the nature of the gated content. Namely there's two criteria used to describe content in each patch:
- content quantity (objective trait)
- content quality (very subjective trait)

Let's describe each of the patches using both criteria stated above:

1) Patch 3.0
There's one large raid (Naxxramas) and two small raids (OS, EOE). In addition, there's the leveling to be done, and pre-raid gearing, which "adds" a couple of weeks to the content duration, if taken at an average pace. Therefore we can conclude that the amount of content to be done in 3.0 is moderate.
The quality is fine, however we should note that Naxxramas, which is the main raid, is generally considered easy. Many guilds have cleared it on day one, and also got bored of it pretty quickly.

2) Patch 3.1
There's one large raid (Ulduar) and that's it - so from that perspective, there's actually less content than in previous patch. In addition, there's no leveling and pre-raid gearing - raiding starts on day one for most of those involved in raiding previously. Therefore, the amount of content is considerably smaller.
Although this is subjective, there's a general consensus that Ulduar is the best raid in WotLK. Both from the perspective of how mechanically challenging and fun it is, and from the perspective how good-looking and immersive it is.

3) Patch 3.2
We come now to the point of this post. Patch 3.2 has one "large" raid (ToGC) and one small raid (Onyxia). This is very little new content. In addition, ToGC is generally considered the worst raid, and considering it has no trash, it is also the shortest "large" raid out there.
In my opinion, patch 3.2 does not deserve to last the full three months on Frostmourne. In turn, I suggest that the duration of this patch is deserved from 3>2 months.

4) Patch 3.3
Pretty much the longest patch in retail (historically). One large raid which is the pinnacle of the entire expansion (ICC) and one small raid (RS). One could argue, that with the addition of three new dungeons (over the one new dungeon in the previous patch), this patch deserves more time than the previous one. Additionally, it's the final patch, and people may want to get their bis items before being transferred to Icecrown.
Given the amount of content, and its finality, I suggest that this patch length is increased from 3>4 months.

TL;DR:
Make Phase 3 last 2 months instead of 3
Make Phase 4 last 3 months instead of 2

Although your logic is really well thought out, in history, Ulduar was one of the shortest raid lives in the game. People were doing ToC 10/10H 25/25H and stuck doing ulduar for valanyr frags during retail. As for ICC lasting longer....if they want anyone to complete the raid with a shadowmourne, then ya it will need to be longer.

I would honestly make the changes you listed, but I also would do the system like retail did where each wing is released one reset at a time. It makes the race much tighter and wipes more impactful.