Hi Pierre,
I am not sure how old your wife is, but you say she only got diagnosed a year or so ago. It's quite a lot to take in, and it takes time to learn coping strategies. You are fantastic for coming here and trying to find ways to help with your marriage.
I am 40, been living with an NT partner for 15 years, and was diagnosed with Aspergers just a couple of years ago. I for one was aware that I had issues, but I hadn't even been able to connect them to anything, or coherently explain them until I spent a lot of time reading about Aspergers.
I suspect your wife may be similar to me, in that suggestions of spontaneity bring out a "deer in headlights" kind of terror. If it has not been on the schedule for a week, I freak out. As an example, now we are aware of this, my partner knows enough not to suggest on a Saturday morning that we go out for the day. He will say on Friday evening (or morning) "I was thinking that tomorrow we could go to..." and completely ignore my horrified / panicked look. My first reaction is always NOOOO! Then I have Friday evening to calm down and consider the matter, and realise it won't be that bad, and start planning what I need to do. Sometimes he will point out a couple of things that I may like about the trip. On the other hand, he tries not to give me too much time to think about things, or I will talk myself out of them. It is frustrating sometimes for him to remember that he has to drop these 'hints', but it gives me time to process the idea and get used to it.
I second what CaliCat said about your wife maybe not thinking about intimacy if she is caught up in her special interests. It is hard for an NT to appreciate how all consuming these can be. Honestly, sometimes I am so caught up in things that I don't stop to eat or even go to the bathroom, until it becomes overwhelmingly urgent. Even though logically I know I only have to stop for two minutes, and I can come right back, it is like a burning compulsion that I can't leave. It doesn't leave any room for other thoughts.
The best way I can describe it to you is that it is as if I am on an express train, and everything in my mind is going by so fast, I can't see clearly what is out of the window just outside. My special interests can be in my head, so my partner doesn't even always realise that I am a million miles away. Your wife may have a similar thing.
You mention you have read "22 things a woman with Asperger's syndrome wants her partner to know". Has your wife read it too? I found it massively valuable myself, so if she hasn't read it I would suggest she does. It sounds as though you are making a real effort to understand her, which is great, but she needs to make an effort too. Living with Aspergers can be overwhelming and exhausting, but if you understand the whys (and I didn't myself until I did a lot of reading) then you can find ways between you to make things work for both of you.
As a final suggestion, you said she finds it hard to initiate intimacy. You need to get to the bottom of this, if it is an issue for you. Doesn't she like it, or is she just caught up in her special interest, or is she shy about it? My partner likes to say "hey, can we have some love tonight" before he leaves for work, and that prompts me to start thinking about it, so it's not a surprise later on (darn those surprises!) and sometimes I even remember to start things.

Is there something she likes - for instance can you get her reading an erotic novel, so she is keen to start things off herself later? I saw one suggestion once for shy Aspie girls who weren't confident with initiating things verbally or physically, and that was that they should hang a pair of knickers on the bedpost or doorknob, as a signal to their husband that they were in the mood.
You need to learn what works with your wife, but hopefully you have some suggestions from us. More than anything I would like to emphasise that arguing will not help, but mentioning an idea (or question) and then giving her time to process and think about it before asking for an answer will take a lot of pressure off, and may help you find solutions.
Good luck, and I want to say again how great it is that you are looking here for ways to improve your relationship. Let us know if you have any more specific questions, and we will try to give you our "Aspie insights".