Another infielder that could help raise the floor of this team, while providing a solid bat (in terms of average and not striking out) is Amed Rosario. Rosario gives the Mariners more of a true middle infielder (104 games at shortstop and 36 at second base) versus Solano.
Rosario would give the Mariners and infielder that can play solid defense at both middle infield spots, while being a fairly high average, low strikeout rate guy. He can also steal some bases (46 stolen bases over the last three years).
Rosario has been a pretty solid infielder over the last few years. Removing the 2020 COVID year, Rosario posted three straight 2+ fWAR seasons from 2019-2022. His best season came in 2022 when he slashed .283/.312/.403 with a 105 wRC+ and a 2.7 fWAR. He hit 11 home runs and stole 18 bases. He regressed in 2023, slashing .263/.305/.378 with an 88 wRC+, worth just .2 fWAR and only hitting six home runs, though he still stole 15 bases.
Rosario would be a really solid addition to the middle infield group here. He might be able to get a starting gig somewhere else and look to rebuild his value before hitting free agency again (he probably should and will do this). If Rosario wants to be on a contender and possibly play some postseason baseball, the Mariners would be a really good fit for him. Spotrac estimates his market value at a one-year deal worth $6.3 million. I am not sure this would be enough to get him as another team might offer him a starting job and $8 or $9 million, but if the Mariners could get him in that $5-$7 million range, this would be a solid bench addition.