Considering switching from MFW to SCM (& a science question)

Hi Ladies, I have been on the SCM website and this forum for a good part of the day today reading and learning and am so thankful for all the wonderful info.  I am hoping you might be able to offer me some insight.

I have been homeschooling for a little over a year (started in Jan of 2013).  I have a 10 year old boy and 8 year old girl that are homeschooled plus a 4 and 2 year old boys that are “in the cue” for the future;).  We did our first year of homeschooling with Adventures in US History though My Father’s World and overall we really enjoyed it.  I naturally assumed that the next year we would do the next level up (Exploring Countries and Cultures).  Because we began 1/2 way into the year last year, we recently becan ECC (Exploring Countries and Cultures) after wrapping up Adventures.  We are a little over a month into it and I am finding that my excitement about it is waning.  I do love the topic of countries and cultures and the missionary biograpies I think will be great.  Mostly I am not excited about the AIG science that is recomended with it.  It feels very dry and too advanced and is lacking in the Living Book feel that I really want.  As I started searching for an alternative for Science I came upcon Outdoor Secrets and Jack’s Insects last night and got really excited thinking about using something like this instead.  Question #1: Are these books OS and JI designed to be the only Science offered (plus perhaps other living books) until the are finished or do people often do this and something else?  I am trying to get a feel for what it might be like to switch over to a more SCM based Science plan.  

Secondly I’m considering transitioning over to SCM and away from MFW but I’m nut sure what timeing is best to do that.  I was thinking of perhaps skipping science for the rest of the year (since I didn’t like it anyway) and trying to double up on the history (to the extent that we are comfortable doing so). If I do that I think I can finish ECC by the end of this year and then be ready to start fresh with SCM next fall.  Question #2  Do you have any thoughts on this idea?  

Thank you so much for your help!