Slightly late to the thread ...
avon barbel are often in the 5-7 pound range these days ... but as others have said, they can fight harder than double figure fish.
Your acolyte plus feeder rod is best suited to the chub and bream, although will also handle tench and barbel. After all, we catch barbel on float rods and even on the pole!
fwiw I use a max hooklength of 0.2mm diameter (Bayer perlon) for barbel on the Avon - which is the same diameter as your pro feeder mainline. I’ve never felt undergunned with that for barbel to low doubles, in fact I often drop to 0.18.
There are some proper carp in the river, I’ve seen fish that would be approaching 20 ... but never hooked one yet to my knowledge.
The Avon is a bit of an aquarium ... of the small fish - dace, roach and bleak are common. Gudgeon are making something of a comeback. puppy chub abound in some stretches ... and there are also silver bream, skimmer (bronze) bream and “daddy” Ruffe. I caught my first Avon Rudd last weekend, after 30 years of fishing the river, although I understand they are more common in the mill Avon down at Tewkesbury ... so I reckon the fish you are catching are more likely roach.
the common confusions when similar sized:
- roach vs Rudd ... downward pointing Mouth vs upward (Rudd look like they have a Jimmy hill chin)
- chub vs dace ... chub have a really wide mouth and black tint to the fin tips. Dace has A more delicate “pout” when unhooking
- silver bream vs bronze ... silver bream have a much larger eye and a pink tinge to the fins.
- ruffe vs perch ... Ruffe are like a dull green version with no stripes
- gudgeon vs barbel ... gudgeon are a mottled green colour and have 2 barbules only (barbel are golden and have 4). I’ve only caught barbel above two ounces or so ... and that would be a huge gudgeon!
hope that helps
that’s without hybrids of course ... I had a 2 pounder in a Match a couple of weeks ago!
edit ... wrt feeder and link fishing ...
small dace in slow flows are absolute nightmare on the tip.
link works well, but you really need a more sensitive tip than the 1.5 oz, which is the lightest supplied with the Acolyte plus.
But if you’re missing 9/10 bites, shorten the distance from feeder to hook. You may end up at 6” or less.
Good luck