Shame the season ended that way, but it's definitely different. I know in my stories, I've often ended up being too dominant. I'd hate to try and make an interesting story out of Year in my NBA 2K19 MyCAREER!
Congrats on making it through the season, though! I'm trying to think of some of the players that were around at the time that would fit the bill. Mike Dunleavy Jr. might be a solid option for some three-point shooting, from memory he's a free agent after the first year.
One thing to remember is that the Re-Sign Players phase in Dynasty happens before the Sign Players phase (as opposed to real life, where they're all mixed together), so if you're trying to maximise cap space, you'll need to pick and choose who you re-sign carefully. Note that if they're still available come the Sign Players phase you can re-sign them there anyway, so you can take your chances by not making the commitment when you have first dibs on your own free agents if you're comfortable with letting them go, worst case scenario.
You can also try front-loading and back-loading contracts to entice players, or maximise cap space. It won't always work out because players won't necessarily be interested in a contract structured that way, but if they are willing to sign those deals, you can save cap room now to possibly squeeze in another signing, or in subsequent years when other players will be available and you need some extra cap room to go after them.