Sure thing... as long as you arent leaving a trail of destruction across the region then you can do whatever you please in your plot. The OP is a little restrictive now that I've seen how flexible the game is... regional play is very helpful but there is a lot more wiggle room for people to change their playstyle and it still works.
Something that has worked really well for me is to "reboot" my city by converting my "work" (in the form of the population I've cultivated) into money by driving up the taxes to 20%, shutting off everything but power/water/sewer and trash/fire/police/medical and letting the population dry up. Eventually, The positive budget will dwindle, then I shut off T/F/P/M and then eventually also P/W/S until everyone is gone (there should be no negative expenditures so youll level off at +0). Then, bulldoze every inch of the town and restart with a few million in the bank. Your new city will have a population explosion due to all the services you can afford to put in early and you can get going again more quickly than grinding all over. You can also plan better since you can afford the high-cap tier of roads right off the bat.
I also love to experiment... that's the fun of the game to me, the challenge of tweaking and balancing complex, intertwined systems and hit the best numbers possible. You'll fit right in and with a 300k city I'd hardly call you nooby. I think we should all continue to experiment and fine tune our design skills and once I get confirmation that cities won't be lost then we can set in a permanent region for the [5 so far] TypoC players. Or, we could start now and as you said, if one of us gets locked out of their city we could abandon and let someone else "reboot" it and take over... but then they'd be splitting their attention... would they give up their region to the locked out player? Seems like with such a critical bug we should just wait, I think they would fix it soon.
We should definitely trade tips here. What I have discovered so far:
1) The single most important aspect to a city is traffic. It drives the success or failure of all other systems. What I have surmised is that players who have brought in a mindset from previous versions of SimCity where they want to cram as much in as possible will fail because doing so almost always includes an aggregate route system. Because most sims take the shortest route possible, any kind of central cross-through will become crammed and then gridlock the rest of your system. That is because the majority of random point A to random point B via shortest route will include crossing that aggregation. This game is all about quality over quantity. You can get massive density without covering every inch of your region with roads.
Therefore, balanced road systems where a slight change in, say, point A to a given point B results in a different path is best. This calls for some rather unorthodox patterns, or at the very least ones which are purposefully devoid of a route which is intended for majority use. The counter-issue to this, though, is that you need to have at least enough aggregation for your city services to be able to access everything easily. Too tight, though, and those aggregation points will be a useless location for your G/P/F/M since they'll get gridlocked.
What has worked best for me is a "brick" layout where sections are rectangular rather than square and alternate, providing for 3-way rather than 4-way intersections. My latest city applies this concept in a circle format, with 3 rings, the 2 sections between the 3 rings are segmented into 3 segments (think a peace symbol) and the inner segments are divided opposite of the outer segments. Without any public transit, it stayed completely green/no gridlock whatsoever up to about 150k.
Im curious to see what other people have found to work and to somehow combine these ideas. One that Im working on now will use the peace-ring pattern along with another idea where you only place zoning on one side of the road and then put twice as many roads (I believe that person did not use avenues... I'll have to re-read the thread on the SimCity forums). I'm trying to wrap my head around why it works, besides the obvious, so that I can apply that principle to the peace-ring format and hopefully be able to top 300k without traffic.
2) The most important needs are put in order on the UI from left to right... power>water>sewage>(government is necessary to advance the rest)>trash>fire>medical>police>transport>education>land value. When I have money to spend, I go through them left to right... power in the green? Okay, move on to water... etc. The only exception to this is...
3) Develop education before expanding tier 2 F/M/P and putting in recycling. You need to spend money on education anyways, and it's cheaper and more effective to maintain a robust education system for 4k/hour than to expand F/M/P to cover the mistakes of an uneducated population for 2k/hour times 3 services. I usually put in the tier 2 F/M/P first and then don't add anything until much later. I build up my education system first and the default fleet size goes a long way. Later on, say, 150-200k+ I'll expand the basic fleet unit to max capacity and add the response time reduction add-ons for each. As long as traffic is working, I've managed to get 0/0/0 for the fires/crime/death stats and that allows me to focus on the game's meta-elements rather than deleting burnt down buildings every other minute.