Steve: How hard would it be to have an "ignore jump engines" flag similar to the "ignore maintenance" one? If it's as easy as I suspect, why not just try throwing it in for 3.3 to see if people like it? I for one would like to try this - I think it would make exploration and colonization much less of a struggle (from the attention to detail and economic planning point of view).
It would actually be a lot more work to allow for optional jump engines than simply no jump engines because I would have to account for both situations whenever jump engines are currently required. However, I have found a very easy way to get around this. These is now an option on the game window for all jump points to be generated with jump gates. So if you want a game without jump engines, just choose that option.
On the subject of "small" jump ships: one of the things I would like to see is to lower the minimum jump engine size from 15 down to something like 5. I like to build small courier classes, and they end up hauling around a lot of useless jump engine mass (which increases their size), especially as efficiency goes up. If your jump engine efficiency is 5, then it doesn't make a lot of sense to build a ship with jump engines that's any smaller than 75 HS.
For a long time I have stuck to the minimum 15 HS, mainly because I wanted jump engines to be something for larger ships only. As you mention below, Babylon 5 was the main inspiration for the jump engine model and jump-capable ships tended to be fairly large. The White Stars were unusual in that ships as small as that didn't usually have jump engines. However, as you point out, as you get more efficient jump engines the effective minimum size of jump capable ships increases. Therefore I have added a new line of tech that reduces the minimum size of jump engines. Each level of this tech line has pre-requisites of the previous level and a jump drive efficiency tech. So once you have Jump Drive Efficiency 4, you can research Minimum Jump Engine Size - 12. Once you have Jump Drive Efficiency 5, you can research Minimum Jump Engine Size - 10, and so on.
On the subject of battle riders: IIRC, Steve's original vision for jump ships came from Babylon 5. So, from a techno-babble point of view, you should probably think of a jump-capable ship not as a mother ship (with non-jump-capable parasites), but instead as having a portable wormhole generator. This is in fact the way I tend to use them - I park a jump ship at a jump point and it acts as a "bridge" for ships moving between systems. As Steve says, most combat tends to be in deep space, so the mechanics of jump transit is somewhat moot for the battles. From the exploration and colonization point of view, however, the jump/non-jump dichotomy does add a lot of complexity - jump ships are expensive, and therefore limit the number of planets you can be ferrying colonists and factories to simultaneously. (PS - you wouldn't believe the amount of time I spent with the Million Credit Squadron Traveler expansion.)
Yes, that's true. The concept came straight from Babylon 5 with the larger ship opening up jump points for the smaller ships to use. So as you say, its not a battle-rider. Although I guess in terms of gameplay function they are similar as both require a specialised ship to get other ships through the jump point. I regularly use the same tactic as John by parking a jump ship at a jump point and using it as a mobile jump gate. I also tend to build a lot of jump gates within the core systems to facilitate travel for non-jump-capable ships
Steve