Day 3
Start of the day:

Day 3 doesn't bring much of a change. I'm first with 120, Colombia and four others tied for 2nd at 70. No change to coalitions; the top one has 260 points across their four members but hasn't done much in the past day.
Research: I don't research anything on Day 3. L2 AA is available but, surrounded by inactive neighbors, I don't need AA right now and I decide to postpone mass production until I research L3 to save on resources. Likewise with ACs--I know I'm going at least to L3, so no need to research AC L2 if I'm not going to produce any. Day 6 is looking like a big research day for me: L3 AA, L3 AC, and L3 tacs all hitting on the same day. With the level of inactivity, I'm starting to think I might be able to stretch it until then and only start mass production of each unit when I hit L3.
Diplomacy: There was a report in the newspaper of an unspecified spy caught in Oregon, so at least one player is using them. I don't think I need counterespionage spies yet but will add one in the next couple days. Colombia is progressing slowly but surely, finishing off Venezuela (likely inactive) pretty efficiently with 48/1 k/d (that doctrine advantage is huge). Three of Colombia's core cities already have 4 buildings each, and they've built a total of 5 buildings across the four cities they captured from Venezuela, so they are certainly wasting resources and aren't building efficiently. Good for me. They gain a new member of their coalition, Cuba, who has been progressing through the Caribbean islands, picking off Jamaica, Haiti, and Dominican Republic. There are some bombardment marks, probably from cruisers. Cuba also has 4+ buildings in their core cities, so they're not playing very efficiently. They only have 10 coalition wins in 71 games and a PVP k/d of 1.6, but with only 611 PVP kills in 71 games I'm not very concerned. Towards the end of the day I click around the map and guesstimate that at least 30 players are about to go inactive at day change, which is absurd.
Construction: One small downside of starting with inactive neighbors is not having any buildings in the cities I capture, but that's alright. Oil is still my limiting resource so I pick some up after day change while it's cheap, at 11.7. My economy is already strong enough to sustain HT production out of two TPs and I still have 24 hours until I can start HT research, so I'm in great shape there. I continue some Industry investments here and there. As I approach day change I start to plan out my Oil consumption, which is still my limiting resource. I need 4150 to start HT research at day change and need another 4400 to upgrade my TPs to L3. My current stockpile and generation rate of 500/hr + the Oil I'll get for capturing East Texas's capital will give me more than enough so I decide to go for another Oil Industry upgrade.
Production: I start the day with 2 MTs and two more on the way, and continue to produce them all day, topping out at 9 (I could have built a 10th but choose Oil Industry instead). I haven't produced any Tacs and Ints yet, so may have researched them soon, but that's alright. It's harder to make use of those in ones and twos, whereas I can immediately add even a single MT to any ground stack to make it stronger. I'd need four L1 Tacs just to one-shot an infantry, so I won't be using them until I've got a good number.
Moves: Despite spreading my units around, three provinces revolt overnight. I send some AA around to clean up the mess and re-consolidate my main units to continue conquering. One of my over-stacked stacks loses another infantry, and I suspect I actually put too many infantry in it, increasing the amount of damage proportioned to unarmored units and increasing the likelihood that I lose a unit, I think. Annoying, I hate losing units. Towards the end of the day, I'm facing that MT stack in the East Texas capital and trying to figure out how to tackle it. I added two medium tanks to my nearest stack and break out the trusty calculator, courtesy of DxC. The situation:

My stack isn't great, but it's what I've got nearby and I really want this capital before day change: I want the morale boost and revolt prevention before day change, and if the AI takes over at day change I'll also get less cash reward when I capture it. The calculator tells me that attacking with the stack as-is will result in 5 infantry losses--that's not happening. I know I need to reduce the number of infantry in the stack, otherwise they will take too much damage, but I need some for their damage output with the urban terrain bonus. It looks like three infantry is the magic number to minimize unit losses (calc says I'll lose two of them), but there's another issue--at this point, there are only 3 hours until day change, and the calculator is telling me it'll take 3.5 hours to finish the battle. I decide to start the battle with the main stack, leaving three infantry in it, while holding the other 11 infantry nearby to attack once the defending infantry have been whittled down a bit. My hope is that this approach will get me the capital before day change while still losing less than the 5 infantry I'd lose if I plowed ahead with the full stack. It turns out I was right--I'm able to save the 11-inf stack until a few rounds have been fought, after the enemy's unarmored defense has been depleted, then bring them in to finish things off. I capture the capital about 30 minutes before day change, only losing two infantry with my approach--pretty much a best case scenario.
Stats at the end of Day 3: 91/5 k/d (ugh, that 5 hurts), 56/0 provinces