Hi,
If you look at the Easycare site, there is a lot of info there on choosing appropriate boots for your particular horse & situation. There are many different types & basically the best type is the one that fits your horse best. They're also helpful if you want to speak to someone in person about it.
Easyboot Gloves are a great boot, but with no ability for adjusting or fastening, hooves need to fit them pretty perfectly - they can be inappropriate for high heels & flared feet or for people who don't trim little & often, because there's not much leeway for excess growth. They also don't have room for pads, should that be a consideration(with thin toe soles & retracted frogs pads could well be helpful/necessary.
Old Macs are good for general purpose trail boots & are pretty 'user friendly' & easy to fit & use. They are a bit 'clunky' though, as with all the 'high profile'(boots that have an 'upper' around the fetlock) boots & also the high profile ones are more likely to rub if not a good fit and are not the the most appropriate for long/hard riding. Trails or the new Back Country Gloves(Glove shell with Trail upper for ease of fit & use) are other good 'high profile' options for light riding.
Cavellos are a cheaper boot, similar to the Easycare Trails. You say you've already used them & found they rubbed him tho. Again not designed for hard riding. I've found them hard to fit personally - they have been problematic even when the hoof measurement(there's only one for them) is spot on, they moved on the feet or rubbed, and I felt the uppers were a bit firmer/less yielding than that of Trails or Old Macs, so perhaps more likely to rub.
Boas are another to consider, but they're best for a more upright, high heeled hoof form, so if he's still that way, they may be appropriate option too. Renegades will apparently be more likely problematic for that kind of hoof form, but not speaking from personal experience on them. Easyboot Epics are a great general purpose boot too, but can be a little hard to get on & off.