Just another perspective.
I fed my ds until 2.5 and have no regrets about it, he gave up gently and easily when he was ready. However, he also was a bad sleeper and co slept from 9 months until 2, so at 2 I night weaned him. He retained his 'comfort' bedtime milk for another 6 months until he swapped it for a cup (took only a week in the end once I decided to make the change), but he did start sleeping through in his own bed. Might night weaning be an option for you? It is a bit gentler than total weaning, especially when it is so important to them, but also serves as a 'first step' and makes weaning easier IME. Google Jay Gordon night weaning for some methods. I found them useful, and you can adapt them to your own situation.
My dd is currently 18 months and still breast feeding quite a bit, and comes in when she wakes. She is just starting to go longer in her bed (toddler bed also), starts the evening in it, wakes at midnight, then back in until 4 or five. I'm happy to continue with this as she needs it though, and from my experience with ds I'm more relaxed about it because I know it does all work out eventually 
What I'm saying is, he's still young, you can take your time, each phase seems worrying when your in the middle of it, but they do grow up and move on more easily than you think, with some encouragement, so don't worry! Also I think teething can play a huge part in comfort feeding around this age, and when they don't have this and can do more generally they do become less interested.
As for speech, that sounds within the realms of normal to me - they do tend to develop in bursts, you may find his word count suddenly explodes. Just keep doing all the normal things, songs, books etc, and you can always talk to your HV for reassurance. I think it varies widely what children are able to do verbally and physically at this age, they all go at different rates.
Potty training - it sounds like he is getting some awareness which is great - I would introduce the concept but let him go at his own pace. My ds had no notion of wet and dry and didn't train until 3.5, did it very quickly and with no problems, despite a lot of angst on my part over the preceding year 
My dd at 18 months has already done wees in the potty, and knows when she's wet and needs changing. I am offering her the potty at changes but she is still so young we are taking it slowly.
Anyway, a lot of waffle there hope some of its useful 