Just like baseball is a game of statistics (as the QM points out in the opening of his post about Ratings, Attributes and Traits), this quest also is.
So in the spirit of the game, here's an analysis of our options.
In the "what type of hitter" options, there are 3 types of boosts and 3 types of penalties mentioned:
-Boost > small boost > minimal boost
-Penalty > slight penalty > no penalty
We're not sure what their numerical value is, of course. It could be 50 > 25 > 10/0 or 40 > 20 > 10/0 or 10 > 5 > 1/0. Or anything else. Who knows? For the sake of having numbers to illustrate stuff, I'll pick one (and I guess I'll go with the first set), but like I said, it could be completely different.
Either way, these are the options, rearranged for better comparison:
[] Eagle Eye. You will receive a boost to your Eye and Avoid K's ratings. However, you will receive slight penalties for your Contact and Power ratings.
+50, +50, -25, -25
[] Professional Bunter. You will receive a boost to your Bunt and Speed ratings. However, you will receive a penalty for your Contact rating.
+50, +50, - 50
[] Hitting Machine. You will receive a boost to your Contact rating but a slight penalty to your Gap Power and Power ratings.
+50, -25, -25
[] Slugger. You will receive a boost to your Power rating but a slight penalty to your Contact and Avoid K's ratings.
+50, -25, -25
[] Warning Track Guy. You will receive a small boost to your Gap Power and Contact ratings and no penalties to other hitting categories.
+25, +25
[] Speedster. You will receive a small boost to your Contact, Speed, and Base Stealing ratings. However, you will receive a penalty for your Power rating.
+25, +25, +25, -50
[] Balanced. You will receive a minimal boost to all of your hitting categories and a slight improvement to your L/R Splits.
+10, +10, +10, +10, +10, +10, +10, +10 and +10 (maybe?) for L/R Splits
Notable things from the QM's Ratings, Attributes and Traits post:
-Contact: perhaps the most important rating
-Power: easier to develop than Contact
-Eye: affects OBP (one of the most important baseball stats)
-Avoid K's: works well with Eye
-L/R Splits: starts with a 15% negative modifier vs bad matchups
-Running Speed: meh on its own, works well with many other ratings
-Base Stealing: dying art
-Bunt: almost dead art
In light of this, I'd say that, from a general and rather dry and limited point of view, Eagle Eye is better than Professional Bunter, and Hitting Machine is significantly better than Slugger.
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Moving on to "what type of fielder are you" options, there are only one type of boost and one type of penalty (slight), here:
[] Vaccum Cleaner. You will receive a boost to your Fielding Error rating but a slight penalty to your Fielding Range. +50, -25
[] Desert Eagle. You will receive a boost to your Fielding Arm rating but a slight penalty to your Fielding Error. +50, -25
[] Outfield Clipper. You will receive a boost to your Fielding Range but a slight penalty to your Fielding Arm. +50, -25
[] The Great Wall. You will receive a boost to your Catcher Ability and Game Sense but slight penalties to other fielding categories. Only pick this choice if you have selected Catcher as your position. +50, +50, -25, -25, -25
[] Sixth Sense. You will receive a boost to your Game Sense but slight penalties to the other fielding categories. +50, -25, -25, -25, -25
Notable things from the QM's Ratings, Attributes and Traits post:
-Fielding Error: starts fairly high and every 10 points in it will decrease 1 error per season on average.
-Fielding Range: very much affected by the Running Speed rating
-Fielding Arm: useful to a lot of positions, including Catchers (who would get a penalty to it)
-Game Sense: affects a loooooot of things, including our time at bat
In light of this, I'd say that, while the first three options are numerically equal among themselves, Vacuum Cleaner is arguably worse than the others. As for the latter two, The Great Wall is evidently better than Sixth Sense, but if we choose it, we're limited to Catcher as a position.
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I'll likely make a plan in a few hours, but maybe someone else will find this useful in the meantime.