Now I've waffled on (one of my skills :-s), can I actually ask a question!
What you have said above is interesting. I have inattentive-type ADHD. It's been diagnosed and I have very clear symptoms that indicate this.
My son is autistic and has ADHD and we have loads and loads of ADHD and autism in the family. Interestingly, I do genealogy and recently spoke to a newly found hird cousin on the ND branch of my tree, and she had ADHD, her son had ASC and ADHD and another cousin she'd spoken to also had ADHD! Anyhow, I digress!
What you've said above is interesting. I definitely have ADHD but also have loads of autistic "traits" - periodically I do an online test (the AQ test?) and I ALWAYS come out as borderline. Is it worth taking this further to an assessment, or is it pretty clear that I am not autistic if I am not meeting the AQ test "level".
I also thought that autism was diagnosed based on a triad of impairments? Has that changed?:
 Communication — the ability to express oneself, both verbally (what we say) and nonverbally (our facial expressions, our ‘body language’).  Social Interaction — the ability to interact appropriately with other people, including interest in other people’s ideas and experiences, and the ability to empathise (understand) other people’s feelings.  Imagination — the ability to think and behave flexibly and creatively, including tolerance of change, imaginative play and adaptive responses to situations.
The thing that always gives me pause is how much like my DS I am (and a friend of mine who works with SEN children also said that she thought I was autistic). I've always struggled socially but I do like socialising but prefer 121. I often need a decompress from too much socialising especially in a group. However, I don't do routine - I get very quickly bored with and struggle to maintain routines (ADHD :-)). I quite like change (thanks newness and novelty :-)) but I am also not spontaneous and changes to plans can really throw me. I need a bit of time to adjust to a change to a plan, it can make me anxious. I like to plan (even though I find that difficult) and know what is happening and I don't like surprises as they don't often meet my specific expectations! I don't have one special interest (my DS has multiple but most have been lifelong) but do get very into topics or interests for a varying period of time, and I often don't want to do or talk about much else when I do :-s There's so much cross-over of "symptoms" and conflicts where ADHD is also present, so how do you tell?!? Not asking for a internet diagnosis (:-)), just wondering whether it's worth pursuing an assessment or not.....
Sorry for the long waffly message!