Welcome to the Cisco Learning Network!
Thank you for sharing with us your CCIE SP lab experience. Its not an easy task to pass any CCIE lab exam, but at the end of the day feel proud of yourself, since you took it. Now you have a better sense of what involves passing this exam.
I am sure next time you will pass! You can do it!
Furthermore, if you believe there is a section of the exam you wish to raise an issue on. Keep in mind you can open a case with the Certification & Communities Online Support team at the following link: https://ciscocert.secure.force.com/english
You can submit your feedback to them for further investigation.
Here are some tips that may help you.
First of all, taking the SP expert-level exam for your first attempt is something I never recommend. The SP exam is a monster. Beginning with R&S, you, in the first place, build a solid foundation for SP in terms of knowledge and TS and configuration practice, and, in the second place, you get accustomed to the exam environment and timing.
But since you decided to begin with SP...
There are three key points about the troubleshooting section. The first one is time management. Don't get stuck. If you see that you have no idea of how to approach the ticket in a systematic fashion, just move on to the next one. Do not waste time running in circles and trying this thing and that one. If you have one ticket unsolved, just move on to the DIAG. You probably can safely leave even two tickets unsolved if you do well in DIAG and CONFIG.
The second key point is to focus on the problem. Do not waste too much time exploring the "huge network", in fact I think that's completely unnecessary for the TS. What you need is to focus on the exact problem and systematically work on the detection of the root issue. If you have no idea of how to approach the issue, then knowledge of the network won't help you in any way.
The third key point is knowledge of "tricks". By "tricks" I mean either things poorly documented, or some specific cornercases. I'd say you are unlikely to be tested on poorly documented things, but "cornercases" is the hobbyhorse of all exam creators in all fields of engineering. With this, you either know the trick or you don't know it, and there is not much else to be done. If you don't know it, you just fail the ticket, period.
You may wish to try the TS lab in my workbook which I tried to prepare in the "Cisco fashion" - introducing tasks on seemingly commonplace topics, but with some tricks and pitfalls. Maybe I will even make a video on how to solve it.
Overall, back in summer I did not find the TS section in the real exam very difficult. If my memory does not fail me, I failed only one ticket in either attempt - although I did not follow my own advice and strived to the end to have it solved.
The Diagnostic section. I also did not find it very difficult. The key, in my opinion, is being able to abstain from examining all the information that you are provided with, and to focus only on key facts, outputs and displays. In other words, the systematic approach is again your friend. The major drawback was that the interface of the DIAG section was poorly (IMO) organized, making it cumbersome to switch between different pieces of data. I believe I have pointed that out in my feedback to Cisco.
The Config section looked most difficult for me, but since you were OK with it, I won't say much.
Last but not least, the SP exam suffers from instability of the environment from time to time. Last July during my attempt the servers sorta crushed or something, so they just zeroed out all my TS results, although in fact I solved all tickets but one. So I had to retake the exam, and in that second attempt all went smoothly.
When one takes the exam two times within a short time span, it is tempting to hope that the tasks won't change. This is the hope that I do not recommend to cherish. Better make good use of the available time to work on your weak points.
Good luck with your next attempt!