XTRG - "House Rules" is one of those topics where you're going to get a very diverse range of opinions. Some folks use them, others enjoy games where anything goes. What it really boils down to is the type of PBEM game you and your opponent are looking for - and both players need to want the same type of game.
In my ongoing PBEM with L_S_T, we agreed to a number of house rules at start to try to have a somewhat historical flavor in the game, and added and modified some as we went along. We're still going strong, 5yrs into it:
Here are the initial house rules we agreed on:
- No 4e naval bombing below 10k
- Dot base invasion/paradrops
- Restricted units must pay PPs to cross national borders
- Sweeps at 2nd best maneuver band
- Airfield/port/industry attacks limited to one air unit per target base in 1941/42, two in 1943, three in 1944 and four in 1945
- limiting squadron size change to a max of 36 planes
We also started with the 8 Dec scenario, which eliminated a number of 1st turn house rules such as only one port attack, landing at Mersing etc.
Many folks don't have any house rules at all - and it seems to work for them too.
+1 - Be candid up front, agree on what you both want out of the game.
Have used pretty much the list above in the past to help define with PBEM.
Concur with many above posts, the "game" operates just fine without House Rules. I see HRs more as shaping the "kind of game" you want to have, historical game or period game. I like to invest my time closer to simulating historical constraints and outcomes. Others prefer to play within the games period parameters without the burden of some of history's constraints. Both are cool, just know which one you prefer and find a like minded opponent.
As an example, (for AI play only at this point...and I did it in my last PBEM and never even bother to tell my oppenent) as Allied I heavily restrict #s of TFs and LCU moves the first 30 days, reflecting confusion, poor communications, need to prioritize, mobilization challenges, et.al.. I've modified LSTs Mod to create a wave of IJ merchant ship mobilizations and initial locations over the first 90 days of the war (I think the US would have noticed if by some chance every IJ merchant ship was in port, mostly all in Japan, on 7 Dec, fully armed up). I don't allow US planes to base at UK/Commonwealth supported airfields or the reverse (unless Sqdn is a shared airframe type available to both). If I had a like minded opponent IJN and IJA planes would not mix on their airbases (am fine giving the AI that edge, it needs it). etc, etc.. I like to play within history, just me.