My English was also poor; in fact it was IELTS 6 and it wasn't enough for a post-grad program that I applied for (6.5 minimum). I negotiated with the College that I will take 1 semester of their ESL course, improve my language, take their internal academic language test afterwards and I am to be admitted to the main program IF my score is 6.5 or higher.
Originally I did not prepare for IELTS very well, I was lazy and overconfident. Upon arrival to Canada, I ran straight to the College nest day and took their internal academic test without any preparation, WHICH WAS MUCH EASIER than IELTS. I passed it, resulting in full refund of ESL tuition and was admitted to the main post-grad program right away. Needless to say that ESL faculty and the Office of Registrar were shocked but they couldn't refuse, these were their policies (I think it was 10 business days after the ESL starts).
Regarding the presence of relatives in Canada - it depends. First of all what's the level or relevance and I'm sure that looking at a bigger picture, the Officer will be considering if Canada is interested in such a candidate - educated, experienced, young, etc. That point I would clarify with an immigration lawyer. Keep in mind, the very first application to come to Canada is vey important. You better have all your ducks in a row for that first attempt. It may decide how the Officers are going to be perceiving your future applications.
I had my PR rejected once, divorced, married and re-applied 1 month after and eventually received the PR at the end.
So, everything is possible, you just need a professional to take care of it.