I've been at the Old English for 18 years, and the pronunciation is an area that I'm particularly interested in. I read aloud a lot I want to get a natural sound. Basically I want to go Jurassic park on Old English, of course (to stretch the metaphor) some DNA will have to be supplied from modern organisms or synthesized (they recently found out that t-rex was covered in feathers). It's a thrill reading what people had to say back then in their own language, but I find it more of a thrill to hear.
Only relatively recently did I find out that the long and short vowels were the same quality. Up until then I pronounced u as in book and in hoot, and i the way you described it. Weirdly, I found ǣ to be the easiest vowel. I'm from London though and we have long and short ǣ in our speech variety. 'Mad' is pronounced with a long vowel, and 'fat' with the same vowel just short. 'Batman' in my accent has both lengths of the vowel.
I've been practicing the short high i and e for a while now. Bit of a mind-bender in the beginning, but slowly getting used to it.