This is a great idea but I have some modifications to it:
1. The divisions shouldn't be only (South, Puntland and Somaliland), I think it is better to divide it into 5 regions (extreme South "Juba" with Kismayo as regional capital, North East "Puntland" with Bosaso as regional capital, North West "Somaliland" with Hargeysa as regional capital, South west with baidoa as the capital of the region, and Center+South East with Mogadishu or Jowhar as regional capital)Not to forget Mugadishu as the capital of the country, but I'm not sure if it is OK to be regional and Federal capital at the same time.
2. The part that says it is mandatory to re-unify, will kill any agreement before conception in the Somaliland side, So any region that would like to separate have to do a referendum with more than 60% in favor of secession ( I heard they did a referendum in Somaliland, but it is better to have one with international supervision.
3. I believe that 10 years is too long, so if it is changed into 5 or 6 years it will be better.
4. During the first 3 years a regional election should be conducted with international supervision, and every region should divide itself into electoral districts to make it fairer for every group within the regions.
5. After the elections which include parliamentary and an upper house of "Elders" elections a transitional period of 2 years will follow to form a conclusive Federal Government.
6. All hostilities should end immediately or "else", with emphasis on ELSE.
7. Your last three points are more than perfect.
8. All international economic assistant to individual regions will be measured according to the following points:
• Democratic freedom (e.g. multiparty elections, freedom of speech, free media, etc..etc...)
• Government performance in the economy, education, planning, Security, Law etc...
• Good relations with neigbouring regions.
The problem with this idea is how will the regions look like, don't forget that there is a border issue between somaliland and Puntland, and if this plan in a strange twist of fate becomes a reality then there will be border conflict between all the regions, but I think the only solution is to include the border drawing in the elections.