Again, to accurately answer this would take a time sucking analysis, (The FO awards doc is 130 pages of raw data. No thanks.) and better is like beauty, it's in the eyes of the beholder.

To some commutable is best, others high credit per day, me long two leg days, etc. etc.
A quick glance at the pairings looks like both have a smattering of everything.
If the company posts these kinds of stats in a doc somewhere, I don't know where that'd be. Maybe one of the other regulars in the thread might know.

When bidding is open, say @ the 12 of the month, we can use the scheduling system to filter pairings for various parameters

an example would be something like: How many 4 day trips in EWR start after 10 AM and average 5 hours credit per day min. ? Better isn't one of those parameters. Not sure if you can do this for bases other than your own, never tried.

The Pilot info page from Oct shows EWR with 62-66 anticipated FO lines and LGA with 117-121, so I guess one could infer from this that there's more to choose from in LGA?

Having said all that, you'll start on reserve and have little to no control over your schedule, during that time you will have access to all of this and can make your own observations and system bid as needed. On reserve the trip "make up" doesn't matter much as most of the time you get pieces of a pairing as opposed to the whole trip, (or at least I did in LGA), as well as quite a bit of out of base reserve.