Hey Aaron,
The problem you are having with long login times may be one that can be resolved. If it is truly a random issue, it may not have anything to do with your hardware.
Try this:
- Go into System Preferences -> Users and Groups -> Login Items
- The right hand side of the window has a list labeled 'These items will load automatically when you log in:'. Make note of any items that are started at log in and remove the ones that don't need to load at that time.
Also, there is a program called Launch Control that allows you to much more closely manage the processes running on your Mac. Control extends to the following types of processes:
- User Agents
- Global Agents
- Global Daemons
- System Agents
- System Daemons
I don't recommend making changes to any but the first category unless you are familiar with the processes your Mac needs to function properly. Also, don't disable any processes that have apple in the name unless you understand the effects. That said, you should look for software you have installed that may have jobs running that you did not expect. For instance, Adobe and Google both place running processes on your system without you authorizing them expressly.
Enableing and disabling jobs is as simple as checking or unchecking a box; so, Launch Control will not require you to learn any terminal tools. However, LC is just providing a GUI into work you can perform in a terminal.
While I'm writing this, my Mac has 342 processes running, and I keep a close watch on what runs automatically on my Mac.
As a last thought, you may want to open a thread on another group that more directly addresses slow downs on Macs. There is almost always something that can be done. Hope this helps.