I've been a vegetarian and a Buddhist for over 20 years, so I can only give my personal opinion - I wouldn't want to influence anyone else. when I became Buddhist, meat eating just kind of dropped away, I didn't have to make a big effort to give it up. Yes, for Buddhists there are ethical issues about eating meat, as one of the Buddhist precepts is 'do not kill' and this is considered to mean don't kill any living thing if you can help it. In fact, many of my Buddhist friends are vegan ie they dont eat eggs or dairy products either. I know it's inconsistent but I don't myself go this far every day, though I'm happy to eat vegan quite often. I just try to do the least harm I can.
There is quite a lot of evidence to suggest that eating red meat is one of the factors influencing the development of bowel and colon cancer, because the meat stays in the lengthy human bowel system for a long time and this is bad for you. A balanced vegetarian diet will provide all the nutrients you need to stay healthy, and with all the fruit and veg you'll like to eat will probably keep you slimmer, so long as you watch the content and intake of fats etc. If you can't have dairy products you can try all the vegetarian alternatives, eg eggs, soya products, Quorn, tempeh, tofu, nuts, seeds, pulses (lentils etc) which are all excellent sources of protein. Anyway, in the Western world we've all been brought up to believe we need very large amounts of protein to stay healthy and it's just not necessarily so. i've just had my annual review with the doctor and at the age of 68 I've got very low blood pressure and no other health problems.
Also, to produce animals for meat is a process which occupies enormous amounts of land and energy, compared with growing vegetarian food, so is less sustainable in the long run. and I'm sure you know that many fish are endangered so not eating them is helpful.
You sound to me as if you are nearly there already - remember, nobody HAS to eat meat! Get a good vegetarian cookbook, or research some of the many recipe sites in the internet, also look up the British Vegetarian society website etc - ther's plenty of info out there, thank goodness for the internet!