Rick,
Look out, 'cause here comes some free advice.
I worked three years in Tenerife, and visited golf courses Gran Canaria several times. In my professional opinion, good bentgrass greens are possible on Gran Canaria, given the following two conditions:
1. The proper sand and peat are imported. The Canary Islands do not have anything usable for golf greens. Even if you do find the right sand, plan on sifting it yourself on-site, because you won't get the correct particle size distribution. The crushed volcanic rock, or "picon", as it is called, will support bermudagrass with no problem but bentgrass hates it. Peat will absolutely need to come from overseas.
2. Have sweet water. Arid as you are on Gran Canaria, sodic conditions quickly develop. As with the sand, the bermudagrass will readily support it but the bentgrass languishes. Best is a dual irrigation piping system, separating the greens from the rest of the course.
I never had any serious problem with insects on Tenerife, either in bermuda or bentgrass, a few cutworms, no big deal. Also, due to the low humidity, fungal diseases were absent. The only weeds were some Poa in the bermuda in the winter, controlled with simazine, (but if you've got paspalum you can control with salt), and the ever present encroachment of bermudagress into the bent greens.
For greens in the Canaries, I would simply do a dwarf bermuda right on the old crushed lava, use any water available, and have no problems. The winters are so mild there that it won't even go off-color, only slow down a little. But I know how difficult it is to convince the locals of anything but bent on greens. It's a Spanish thing.