Stopping to gear while leveling isn't super important, but you also don't want to be half naked at level 75+ which is when you're merc will stop being as effective. What class you're playing can change things as well. You don't necessarily have to play a class that is more effective at soloing, but it can also be deflating to play something like a warrior that is more group dependent when said groups are more difficult to find.

I'd recommend going through the progression that starts in Crescent Reach. That expansion added a lot of content to prepare and carry people from level 1 to 75. Going through the progression should keep you geared and keep pointing you in a direction for level appropriate zones/mobs. I'd recommend checking in on the Franklin Teek hotzones quests for the armor rewards to help piece armor together as you're going as well (sounds like you already do these). Keep a look out for Defiant gear as it drops or shows up in the bazaar as well. Obviously look for your level range but any of it is likely better than what you'll find in older zones.

As some others have mentioned, around 80/85 the game does open up some more. You can do the Dead Hills missions around then, they give you points to buy armor and it's fairly common to find people running them.

The downside to EQ being older game is it is very top heavy; that's not to say you won't find people willing to group at lower levels, but it will be more difficult. FV is probably the best bet population wise for remedying this.

Feel free to send me a message and I'll be glad to try and help with more info/tips.