I joined this board a week or so ago to explore the option of the new Ancients program for our family in 2010-2011. Since then, I'm really feeling the Lord leading us to switch to HOD next year. I'd love some help with placement

We started with SL and then switched to MFW 2 years ago. I love MFW in so many ways, and the year we did Adventures was perfect, but the large target age range was hard this year in ECC with a 2nd and 3rd grader (low end of the age range) and I didn't fell like we would do well in CtG next year, so I had pieced together a later American History program instead. Then we discovered HOD!
Let me intoduce my kiddos. Oldest, M., just turned 9 and will be 4th grade next year. She does very well in language arts, has recently read such books as Ballet Shoes, Sign of the Beaver, and The Saturdays. She loves to write (though she has a tendency to use a bad pencil grip), can do studied dictation, spells well (she placed in level D of Spelling Power but after 6 weeks never got a pre-test word wrong so we ditched it since it was wasting our time), and is finishing up PLL. Math is sometimes a struggle, and she will finish Singapore 2B by summer.
Middle, L., will turn 8 late summer and be in 3rd grade next year. She, too, loves to read, such books as All-of-A-Kind Family and Boxcar Children. She does not like writing or copywork, but that may be b/c she is often in a program that is above her age. For example in ECC this year she tried doing the bible verse dictation and it had her in tears, so instead we stretched the verse copywork over 2 days and that has been OK. Her spelling is...well, it needs help. We are using Queen's Spelling through Copywork, which is the first thing that has produced any results without frustration. She is in the middle of Singapore 2A for Math. She has not started cursive writing. She has struggled with her overall attitude toward school this year. She is extremely artistic and creative.
Youngest, A., is finishing up MFW K. I'm planning on doing MFW 1st next year with him (middle child thrived in this program but she is very different) so for now I don't need any advice

So, at first I thought Preparing for the girls next year, but now I'm leanng toward Bigger with the Extension pack. That way younger dd will have something really on her target level, oldest can fly independently with the extension part, and we can do a bit more American History, which we would love to do. The only downside is that oldest would not finish the entire history cycle before HS, but I'm just remembering the scripture verse about each day having enough worries of it's own!
Thoughts? Thanks!!!!