I believe that you can wean slowly - you have tons of time.
Perhaps the first step is to stop pumping for the bottles. Just let all bottles contain milk. Then you can work on the actual nursing sessions. Most of what i've read suggests giving each step about 5-7 days before going to the next. So, make all whole milk for a week, then remove a feeding for a week, then move on. If you pay attention to your daughter's response and behavior i think you'll find it can happen naturally.
Using a bottle for longer isn't going to hurt her. However, you could start trying her on a cup for some of the bottle feedings. Maybe give her a sippy cup with her meal, instead of a bottle? Slowly move from bottle to cup. If she is at a table, you can even start her on a normal cup at this age instead of a sippy cup.
As to night time nursings and weaning, i think it would be easier to first decouple the nursing and the putting down. While we were preparing for this step we starting nursing, and THEN changing diaper, brushing teeth, getting in bed. We also started having me nurse, and then having dad put her down.
Additionally, when we were trying to eliminate night time feedings, dad went in to calm her instead of me.
It may be painful for a few days to transition. However, i think it should end fairly quickly if you stick to the plan, and i think it would be better to introduce the changes slowly over the next five months than try to do them all at once in May.