I would suggest rushing in an amount (maybe zero) that meets your own personal level of comfort.
There is no undo in clash, be sure of any building/upgrading decision, especially your TH upgrades. This is rule 1 to upgrading. Maxing may not be "optimal" if you know what you're doing. However, it is an easy/safe strategy that works very well and is decent baseline advice.
That said, defenses do not matter in clan wars before TH8.
There's no reason not to go straight to TH7 (or TH8). This is true even if you don't war. Farming is better each time you upgrade your TH once you've upgraded your camps and farming troops. Loot penalty, especially since the matchmaking changes does not exist in a meaningful form. I say TH7 as everyone can attack well there in Clan Wars with Dragons. TH8 and higher require some skill to have reliable results. Obviously, upgrade your farming troops as you go, and flesh out your base once you find a TH that you want to stay at.
If you don't war, it's probably best to wait to upgrade (past TH7) until one of the following resources doesn't have enough work.
- Gold
- Elixir (if your storages are permanently full, even if you still have lab work to do, that's a sign to upgrade)
- Dark Elixir
- Builders
- Useful Lab (see lists below)
Note that you will quickly run out of things to use elixir on fast enough if you're farming a decent amount. You will have to choose between wasting that elixir or upgrading. Once you're TH9 or higher you can use every drop of elixir that you farm.
Note: Farm for heros at TH9 or higher. Do not farm for walls if heros are not maxed. You will get a lot of walls done while farming for heros, but the reverse is not always true.
I'd argue to wait on wall farming until TH9 also. You'll quickly finish out level 8 walls if you're farming for heros, regardless of what level you had before you got to TH9.
Maintaining Offense > Defense requires TH upgrades before full max Defense. This is a useful thing to maintain for Clan Wars. If you max both at a given TH, then you've brought your defense up to your offense. This is a reason that players new to a TH experience a challenge increase at each TH. I'm not suggesting rushing like the below points, but at a minimum go up slightly before everything is maxed so that you can establish the next level of offense while you finish out the last level of defense. How much "slightly before" is right for you depends on your preferences.
There are strong reasons to continue on to TH9 quickly if you're an experienced player or have a fast learning curve. If it is a first account, stopping at TH8 to learn to Hog and mastering some Clan War basics can be a good idea. Everyone will have a significant hump to get over at TH9. Namely, getting heros to a reasonable level and being able to 3 star strong TH9s. The sooner you start this hump, the sooner you are done with it. Leveling heros is easier to do if it's spread out rather than something you have to do all at once. Level 15 heros are 52.5 days each. The sooner you unlock the Archer Queen and start to work on her, the sooner you'll be able to attack TH9s well. Also at lower THs you will generally have more elixir than you know what to do with (especially if you max your walls before upgrading your TH). By being TH9, you can upgrade a few walls with elixir (warbase junctions to max! before other walls to lower levels even) and put that to a valuable use, saving yourself future farming time.
You do not need every lab upgrade at every TH. You will generally bring a focused army that uses a few troops. There is no reason to wait for every lab upgrade if you have idle builders (or if you have the key troops even). If you realize you need/want a troop that's not on the lists below, do it, don't feel restricted, these are the bare minimum lists. I would suggest you go with War Option A first as it works at TH8 and is probably better than Option B at TH9, but War Option B is slightly less lab time.
Core Farming Troops to level before you upgrade your TH
- Barbarians
- Archers
- Minions (if you use BAM, if you barch, these are not important)
Must have war troops (ok to wait to level until you stop rushing, also ok to do as you go)
- Wizard
- Wall Breaker
- Jump
- Poison
- Golem
War Option A - pick this or Option B first (works at TH8 and TH9, probably the better choice today)
War Option B - pick this or Option A first (works at TH9, slightly less lab time)
- Rage
- Balloons
- Lava Hound
- Haste
Good to Have
- Minions (cheaper funnel creation, BAM farming)
- Giants (storage farming and surgical Hogs)
- Healer (AQ walks)
- (maybe) Goblin (can help farming a bit or TH9/TH10 war base cleanup as these are higher dps/housing than wizards, but you'll only ever bring at most about 2 in war, so low value)
You may notice that some troops aren't on any of these lists at all, namely Goblins, Dragons, Pekka, Valkyrie, Witch, Lightning, Earthquake. Those troops can be skipped and you'll still have everything you need to attack well with multiple styles. Leveling Dragons can assist with filling War CCs, but if you're willing (and your clan is ok with this) to contribute Lava Hounds instead you won't need Dragons at all.
(Advanced CW) Much like some troops are better than others, some defenses are better than others in CW. To the point where
upgrading your TH so you can upgrade the key defenses is better than staying at a lower TH and maxing less key defenses.