has anyone here ever succeeded to any degree at a Hawaii team at division 2? Just how hard is it?

It's really easy

Heh.

titles have been won in Alaska, and Hawaii is easier, so I'm assuming it's been done

As I wrote you'd be alone. You need to find the best situation, it's either BYU Hawaii, Chaminade or Hawaii at Hilo. Now that I know Pepwaves and Emy are making Central Atlantic so tough, I hope you join us. We have solid coaches.

But are their enough recruits in HawAii to make competitive teams without being able to recruit anywhere else? IS there any thing else you can reach from Hawaii?

1. If your the only team you can own the island which will put a good player on your roster most years.  
2. Recruit internationals and the guys other guys look over.  
You are pretty much gifted at least 1 or 2 stars and if you scout well you should have solid rotation players. Just remember you may need unconventional players.  
Im not the best Hawaii coach but I thought recruiting to Oklahoma Panhandle St was harder than Chaminade.
Here's how I built my Chaminade program if you want a guideline (others that have coached at one of the Hawaii schools please chime in on if you have had any other successful strategies.  
 Year 1 (C prestige)
1. George Kraker-crappy pg to just get an extra body in the next class and to not lose a few $1000 by taking a walkon
2. Joseph Nguyen-defensive deficient but good PG for C prestige that mainland teams looked over
3. James Dotson-mainland SG specialist with obvious deficiencies but a good backup
4. Gerald Berends-decent juco that didnt take much money to grab
5. Arthur Parker-pretty good SF that no one wanted
6. Joseph Ratliff-super deficient player that can be allright as a role player
7. Raymond Alessi-good Hawaiian that I redshirted
8. Jimmie Bernard-well rounded but not spectacular big man

Year 2 (C- prestige)
1. Cedrick Brown-Still has a decent amount to develop.  Was an inelligible.  
2. Jack Rigsby-role player. Struggled to find the sf/pf hybrid we needed. 

Year 3 (C+ prestige)
1. Barry Moore-had to settle for a below average pg from Hawaii after running out of options 
2. Kenneth Thomas-Low starting values but will be pretty good.  Redshirted him 
3. Bryan Rothermel-Inelligible/transfer that still has a good deal of potential.  Potential all-american by sr/5 year. 
4. Charlie Puffinberger-Star that I would have had no shot at if I was in a region with more schools.  Lots of potential left. Another future potential all-american.

Sorry for the long post but pretty much if you are willing to accept a few lower level guys to be role players you can get some stars that you wouldnt be able to get otherwise.  Just be smart with your money.  I also wasnt able to recruit a couple good Hawaii guys that would be open to me as a B prestige so theres a decent deal of good Hawaiians.  

IMO, I struggle greatly at Hawaii. Some seasons Hawaii has great recruits and some seasons there is ****.  I'm the only one there so I do get pick of the litter, but depends what's available. I just now got up to B prestige and am able to get pulldowns from DI which helps. I do a lot more international recruits from Hawaii. some one taught me a few tricks, wait till after signings start and FSS some inland states and get best available. I think it's hard to assemble a real good team from just Hawaii recruits.  Here's my team: http://www.whatifsports.com/hd/TeamProfile/Ratings.aspx?tid=14324