Personally i found solo to be a massive grind. Finding the Merchant and bosses takes longer since you are the only one looking for them. Getting the metals for gear and craftign upgrades takes longer since again, your the only one who can get it and carry it out of where ever it is. And then there is the complete PITA if you get killed far from your current respawn point, and trying to do a solo corpse run/gear retrival is a true experience of frustration. (Tip: get a second strength belt from the merchant asap, so you can do dash and grabs on your marker without getting stopped because you can't carry everything without a belt equiped)

But, doing everything your self is very satisfying in the end, becasue you did it yourself, and you weren't following in someone elses footsteps along the way. So its worth trying it solo at least once.

A final tip, make lots of small bases with portals at stratigic spots when possible and try to keep the mats for a portal with you at all times so you can pop back to your main base and empty your inventory when needed.

Good luck.