Interesting - what features of the professional license did you decide were critical? I feel like I might be in the same boat. Maybe I'll download and play with the trial to pursue that same path.
Match groups. Standard version includes differential pair handling tools. but not match groups, which allows to match trace length for high-speed parallel buses like DDR3.
If you want to try it out, make sure you request an actual trial version (Lite is not a trial, it's just that - limited, but free version).
Also might try calling up my Altium rep along the same lines, but they're typically much less malleable since their license is all-or-nothing.
I only paid for one year-long maintenance subscription ($1800 AFAIR) and they gave the actual license for free (which normally retails for $5k). But my sales rep underscored multiple times that they only made such amazing offer because I'm a hobbyist and a person (not company). I was just very clear that despite me wanting the license, there is no way in hell I would buy it for the sticker price. I actually did try Standard version for a while and was trying to come up with some way to make it work - but just couldn't.
As for libraries - I'm not sure what I mean. I know the deal includes a 6mo subscription to Ultra Librarian, but AFAIK that's a large library of pre-made components, with an option you can pay for to build your own. So you're buying into an ecosystem to make your life easier, but it's not a critical piece of the suite. But the deal also DOESN'T include OrCAD Library Builder - what's that, and what am I missing out on? Is that similar to Altium Vaults or something? Not a necessary piece, just a design accelerator?
Library Builder, like Ultra Librarian - are optional addons, whey just automate creating symbols/footprints/3D models, but once you create them they became just a regular Orcad components that can be managed by built-in tools. So it's a convenience, and not that big one too - I'm now 2 months into my UL subscription, but I've only downloaded 8 files - bundled sub includes 1200 downloads, and each file (symbols, footprint or step model) counts as one download (so up to 3 downloads for full part). I mostly use free Library Expert to create footprints/3D models for standard packages (it supports Orcad 17.2), as for schematic symbols - Orcad Capture comes with excellent import feature where you can create a list of pins in a spreadsheet using specific format, and then you can just paste it into their "New part from spreadsheet" window.
So, don't worry - you can manage libraries just fine using built-in tools that come with any license.