Bilingual Education

My fiancée and me usually don't have many disagreements. The most problematic are water with or without gas, jaywalking - and bilingual education.

The language in question is English. Both, she and I, aren't native speakers in English. She is strictly against it, while I would love to educate my children in English.
Probably right now, isn't the best time to make a decision - at least not based on my level of skill - since I am probably on my worst proficiency level in ages. Except for blogging and movies / shows my use of English is probably close to zero. In a professional context I am using German only. All of my close friends do speak German. A few of my relatives would speak English, but they are too far. So it is more likely that I use a few words in Italian, than in English.

But I would still think, that the benefits outweight the possible disadvantages. Yes, I do have an German accent, but not a terrible one - at least according to my teachers, friends and family. And yes, my German is way more sophisticated than my English is. But that is explained by my profession and education. As a legal professional I work with language, have to be accurate with the words I use and understand the delicate distinctions. I did some legal English, but it takes a lot more effort to do legal work in English, than it does in German.

I think bilingual education has a lot of advantages. The child learns a language almost effortlessly and can be fluent without going through the difficult process of learning words. Also most of the grammar - at least for a moderate use case - is going to be known, without even thinking about it. It is said that bilingual educated children start a little later to speak, but than are usually more fluent in both languages. Since the brain links more neurons to a certain concept, for example the English and German word for "chair" to the concept of a chair, it is easier to be accessed by the brain and therefore better understood.

Also I had some bad experience with my English lessons. We started pretty late in my fifth grade (age 10/11) to learn English and most of our teachers haven't been really my favorites. In 7th or 8th grade, I don't really remember, our teacher was sick and the lessons were taught by our music, sports and art teacher. I don't know, if they had a concept, at least it didn't feel like they had one. So yes, I was really disappointed with my English classes in school and didn't want my children to have a similar experience. And I thought, that I could do it better. Additionally, we usually had really big classes - 25 to 32 students as far as I remember, although usually on the higher end. I did build some foundation in school nevertheless, but really learned to speak and write English when I was studying for the SATs the year before my senior year. I went to my aunt in the US and in eight weeks did learn more and improved my speaking and understanding a lot more, than in the complete 11 years before. I did improve my English further, when I was traveling and working abroad in Nepal and Belgium.

My financée had different experiences. She had great teachers. She did enjoy her English lessons. And she is kind of a perfectionist, being afraid to mess something up. That is also her main concern: Since we aren't native speakers, she is afraid, that we could mess up and the children would learn worse English, than they would if they just went to school.
It is to be noticed, that most of the teachers in our schools aren't native speakers as well. And our "normal neighborhood" isn't really super international - at least not now.

So far it looks like she is in the lead and we won't speak English with them. We might send them to some early language classes (in the US or UK) or bilingual childcare or kindergarten, but no self teaching. I was thinking that we might even find an English speaking nanny or

How do you think about bilingual child education? Do you think that the concerns of my financée are accurate and it is "too dangerous" to self teach our future children and better leave it to the system. Or do you think that even if there is a possibility of failure or at least worse education, it could still be worth to try it?

I am not interested in just having the say for the sake of it. I want the best for our children and right now think that it is better, if we speak to them both, German and English, she could do German and I would speak English.

If you think, that trying to do some bilingual, what would you recommend? Do you have any experience? Am I overlook something essentiell?

Cheers, @andy-plays