The Clear Lake Fencing Club recommends that your electric foils and sabers have two-prong sockets (not bayonet sockets). This is not because two-prong is better, but because it is the club standard, and your chance of borrowing spares from the club and its members or buying spare parts from fellow members is much better if you use two-prong. Nonetheless, a few club members to do have Leon Paul-style bayonet.
The Clear Lake Fencing Club recommends that your electric foils have French (Prieur brand and compatible) points. This is not because French is better, but because it is the club standard, and your chance of buying spare parts from fellow members is much better if you use French. Note that “French” for foils is slightly ambiguous; Prieur or HPC tips must be retained with Prieur or HPC screws, and Sport-7 tips must be retained with Sport-7 screws. (Well, not really. That's an oversimplification. See the next paragraph.) Otherwise, the brands are interchangeable. The club has not settled on a recommendation for Prieur and HPC versus Sport-7 for the parts where it matters. Second most common is German, but it is much less common.
Let's assume you decide to use French. As mentioned, it is alleged that everything can be mixed and matched between Prieur/HPC and Sport-7 except for screws and tips having to match. It appears this is not the whole story, though. Although the inside diameter of all the "French" barrels are the same, the outside diameters are not. The thicker barrels require longer screws to reach what they need to reach. If you use a thin-barrel screw with a thick barrel, it might not thread far enough into the tip to hold it well. On the other hand, if you use a thick-barrel screw with a thin barrel, the ends of the screws will protrude too far and sometimes cause the point not to register, depending on the exact angle of the hit. (This problem, though, is easy to fix; take the offending screw and carefully and gently shorten it with a fine-toothed file!)
The moral of this story is that for ideal results you should have the barrel, screws, and tip the same brand, but that brand does not have to be the same as the brand of the wire or the spring (note that sometimes brand new springs claimed to be the brand of the rest of the parts have to be lengthened!). For second best results, you should have a Sport-7 tip and screws, but if you are not using a Sport-7 barrel you should shorten the screws.
Should you use HPC/Prieur or Sport-7 if you use "French"? The club declines to recommend. The CLFC advised standard is merely "French". What does CLFC mean by "French" - Prieur/HPC or Sport-7? It meant Prieur, the original, but only because CLFC decided this before the others existed. Should CLFC start specifically encouraging Sport-7 instead? Maybe, but this hasn't happened yet.
The Clear Lake Fencing Club suggests that your electric épées have French (Prieur brand and compatible) points. This is not because French is better, but because it is the club standard, and your chance of buying spare parts from fellow members is much better if you use French. However, the similarity between French and German is great enough that substitutions can often be made. Staying with only one system will improve the fit of the pieces and function more reliably.
It is recommended that your tangs be metric-threaded (metric "6x1", i.e., 6 mm x 1 mm per thread), not English-threaded ("12-24"). (There also is a third option for French grips, Leon Paul's unthreaded system requiring a compatible pommel.) The Clear Lake Fencing Club has no standard, but metric-threaded is the most common world-wide, and your chance of buying spare parts from fellow club members is much better if you use metric.
The Clear Lake Fencing Club does not recommend a choice between French and orthopedic (pistol) grips. Coaches have opinions, though, and the most common opinion seems to be that it is harder to develop certain bad habits when you are a beginner if your grip is French. However, most serious competitors use orthopedic grips. The club does not recommend any particular orthopedic grip, and many are in use. If you use one, the club has neither a standard nor a recommendation for whether the nut retaining your orthopedic grip takes an 8 mm socket, a 6 mm Allen wrench, or a large screwdriver.