Easy answer to all of those questions: it depends.
How long to get to 1000 hours of total time? Depends on what flight school you get hired with (if you choose to CFI), how busy they are, how many students you get, how the weather is, etc, etc. For example, I've been flying nearly non-stop since I got here, but that could end at ANY moment (hence the reason my bank account has a cushion in it). I'm more than likely going to break the 500 TT mark this month, but it could drop suddenly and I might only have 600 by the end of the year. There's no way to tell. ME time is the same way. Other than the time you get through a time building program or training, it depends on the job. Some schools are better for building ME time than others. A lot of schools don't even have twins due to insurance costs. Then it still goes back to the students and how many/how often they fly. I've heard of guys going from CFI ratings to 1000 hours in about 9 months, and I know others that it's taken close to 2 years. So, there's no accurate way to answer the question. If you're looking for competitive ME time, 150-200 is good.... for now. The more we see this bridge programs/under the table deals with flight schools, the more ME time you'll need. IMO, it's just upping the amount of money need to land an airline job. It wouldn't surprise me in the least to see the day when you can't fly for ASA or XJT without paying an extra $40K for ME time building and an RJ transition course, which is sad.