With the Fonz wearing a cast, the Cubs have a lot of options in terms of how to best modify the lineup to keep the team competitive and competent. I'm going to present a short list of possibilities - not that Lou will necessarily see it this way - and we can debate and discuss for the next little while. (Not to mention I'm expecting to go on the Jon Miller Show again today to talk about the Soriano injury and its impact.)
2B DeRosa - high OBP, good steady hitting
RF Fukudome - ideal #2 guy, good hitter, great OBP
1B Lee - Deadly combo of power and discipline, even though he's been slumping
3B Ramirez - Another huge bat, great cleanup hitter
C Soto - His power ability makes it sensible that he should be protecting Aramis
CF Edmonds - Should he continue to hit well, he's actually one of the better #6 hitters in the league
SS Theriot - Not enough slugging ability to justify batting earlier in the lineup
LF Hoff/Murton/Johnson - the weak link
Lineup Rating: B+ - It's a hell of a lot better than Cubs lineups in other years of competitiveness - who can forget how bad the Cubs were in '98 and '01 once the opposition got past Sosa and Grace? Really, there are only two near-automatic outs in the LF combo and pitcher.
RF Fukudome - His high OBP and so-far lack of power, plus his respectable speed, makes him a very strong leadoff candidate
2B DeRosa - His hitting ability, mixed with his respectable power numbers, mixed with his strong plate discipline makes DeRosa a great #2 hitter
3B Ramirez - His higher batting average, plus his low strikeouts and high walk totals this season mean that Ramirez might actually be the best #3 hitter on the team this year
1B Lee - He's still mashing the ball, but his incredibly hot start has evaporated. Also, his walk totals are down this year. The Cubs would likely have better production and more RBI opportunities if Lee and Ramirez switched.
C Soto - Still the best #5 hitter on the team
CF Edmonds - Still the best option to bat 6th
SS Theriot - Still too low a slugger to bat higher than 7th
LF Whomever - Still the weak link
Lineup Rating - B+/A- I think this lineup may optimize the team and its talents the most. Switching Lee and Ramirez (at this stage) would probably be a positive for the Cubs.
SS Theriot - Although he gets caught stealing way, way, waaaaay too often, The Riot will likely be Lou's top choice to bat leadoff. To be honest, if he can keep his OBP over .360 and if he cuts down on times caught stealing, I will never complain
2B DeRosa - If he's not using his high OBP to make him an advantageous leadoff hitter, DeRosa at this point is perhaps the best #2 hitter on the team, even better than Fukudome
RF Fukudome - It doesn't really hurt for Koss-Kay to bat here, even if the Cubs would be better served to move him down the lineup a bit
Lineup Rating: B/B+ This is probably the route Lou will take. It's still strong; in fact, the Cubs had such a good offense with Soriano that they'll be good even without him. Colin has already told us that, in the short term, the Cubs are projected to score only a handful of fewer runs without the Fonz, so his loss shouldn't hurt the team too much unless the team becomes demoralized - a prospect I don't think stats people can really take into account for.
Incidentally, if Lou went with the second lineup I created today when Alfonso returns, but inserted the Fonz in the #5 spot (should he still have the ability to hit for power), then that would probably be an A+ lineup and the best of my lifetime. I'm just saying.