After some 25 years, my original role-playing group has gotten back together, using the 4th edition rules. I'm the DM this time around, and much to my surprise, this old crew who had given up on 1e AD&D for ICE's Rolemaster way back when, now quite enjoys 4th edition.

I don't plan this as an edition war by any stretch... rather, I'm asking for advice on stringing pieces of my campaign together.

At the moment, my group is on the final dungeon crawl of Keep on the Shadowfell. They've done quite well and enjoyed, advancing to 2nd level quite easily, and I can see them being 4th level by the time they (hopefully) defeat Kalarel.

I had originally intended to take them straight through H2-H3 and then on through P1-3 and E1-3. I own H1-3, but not the others. However, since then I have acquired both the Reavers of Harkenwold, and Madness at Gardmore Abbey... and I really am more excited about these two than H2-3. Partly because the backstories that my players have developed for their characters fit into a story involving the Iron Circle.

My plan is currently to complete H1, but then to move to the Reavers of Harkenwold, upscaling it to whatever level my group is at the end of H1 (I presume 4th). Hopefully they'll be 6th at the end of an upscaled Reavers, and then I can move them directly into Madness at Gardmore Abbey. I was admittedly not all that keen on the Cairn of the Winter King myself... but that's a personal taste thing.

Anyway, my questions are:
1. does anyone have experience upscaling Reavers? I know it's easily done with 4th edition, but did you change anything?
2. my plan is to have Nazin Redthorn as having the single card that the players start "Madness" with, with him having just commissioned the rival adventuring group to go retrieve the deck for Lord Vhennyk. They won't know about the rival group being commissioned, only that Vhennyk has given Redthorn orders to retrieve the deck. Does this seem a reasonable link?
3. Post-Gardmore Abbey, I'd eventually like to link things to P1, but I may need to do a homebrew adventure to bridge the gap. One possibility is to use Vor Rukhoth or Hammerfast as a setting to cover this territory. I had a thought of pulling the characters more seriously into the Iron Circle's sphere again, but bring it south into the IC's own territory near Sarthel. This is why Vor Rukhoth might play into this a little bit more.

Any thoughts or suggestions? Anywhere from upping Reavers to a 4th-6th adventure, to what to do post Gardmore Abbey?

I'm having fun... which regardless of the edition, is what matters.