As you might expect, Dave gives an excellent response to the question.
I'll toss in a few things I've gleaned from my 1st season of racing & power training...
Specificity: You want your present/current training to reflect the demands/requirements of your events. If you are racing TT's then practice your TT'ing. If crits are the events, then do plenty of microintervals along with speed work and shorter intervals. I know plenty of people doing several group rides/week when their target events are say, a 20k or 40k TT....is that the best use of limited training time? YMMV...
Composition: A corollary to the above, but a say, 80 CTL, can be made up of many, many different varieties of training and training emphasis. My view of CTL is that it is simply the chronic "dose" of training that you are used to....not necessarily how fast you are, how high your FTP is, or even whether that "dose" of training is going to help you race well and/or better. My approach is to tailor the composition of CTL to reflect a) where I am in the overall season from a yearly perspective, b) what my goals are at that time.
As an addendum to composition, what Dave mentions about the best way to rack up CTL is spot on. When I got CTL over 110, I was doing hella lotsa mid-to-high tempo riding. Why? Because the fatigue associated with such rides is quite a bit less than pure L4 (or higher) riding. As a bonus, most people can ride @ IF 0.8-0.9 day in, day out, but few can do 0.9 (or higher) that often (unless of course, they seriously lowball their FTP). Yet the training levels aren't discrete, meaning nothing magically happens at L4 that isn't happening at L3. Mostly it is simply a tradeoff of time vs intensity. Though eventually you need to move up in the intensity scale to keep progressing as you get further up your relative "trained vs. untrained" continuum. Getting back to CTL....now for example, I'm around CTL 95 but with a heavy dose of L4 & L5 rather than L3 as noted earlier...essentially "sacrificing" or "trading in" some of that hard earned CTL from the offseason, for good racing form and maximal FTP development.
Schedule: Hard day - easy day, block training, etc...there are many ways of approaching your schedule on a daily basis. I'd say experiment with what works because while the physical requirements may vary, so to will the practical considerations such as how much time you have available to train or work or school, etc. Personally, I've been on a block training schedule for about 8 months and find it very beneficial.