Eloy's still only 22 and playing his first 46 games in MLB, all while getting hurt. In 24 games since coming back from the IL he has a 264/319/585 line. Since coming back from injury that's a .905 OPS, with a .322 ISO. wRC+ at 137. He averages a HR once every 15.45 ABs this season. Over 600 ABs that would come out to around 39 HRs. Again from a 22 year old rookie. If he stays healthy he's got a pretty decent chance to get to 30 HRs as a rookie, which has only been done 28 times in MLB history (since 1871). Since 2000 a rookie has hit at least 30 HRs 7 times. Those players are Trout, Judge, Pujols, Abreu, Braun, Bellinger, and Chris Young. Pretty good company. If he gets to 500 ABs this season, he would be on pace to hit 32.5 HRs.
As for Collins, even if he K's a ton he is going to get on base. In every MILB stop where he had over 100 PAs, he has never had an OB% below .365. In AA and AAA it's been .422 and .382 over the last 182 games. Castillo with the Sox had a .304 OB% last year and currently has a .289 OB%. Zavala in AAA has had a .267 and .282 OB% that last 2 seasons.