It's not a bad idea and as has been said many other models have this (including mine, though often I wish mine was like yours). The one drawback is headsail sheeting angle and constantly flipping the skirt of the jib inside the lifelines and then having it lean on the shrouds and turnbuckles on almost every point of wind, not just close-hauled.
My H25 is 'reinforced' (if you can call it that) with 1" x 25" plates spanning five of the toerail boltholes under the flange. That's it. The washers on the 1/4-20 bolts aren't even oversized. (I plan to upgrade all this very shortly anyway, but the basic idea will be the same.) But this is a smaller boat (255 ft of sail). By comparison the Cherubini 44 is fitted with u-bolts through the flange and then the flange is supported with a massive L-angle of SS or aluminum and then a 65"-long web of sold fiberglass down to the hull which takes up a lot of room and inhibits access to-- you guessed it-- the u-bolt fasteners. So there is a trade-off.
Your H30, lying between the two, could benefit from an SS L-angle of about 1-1/2" x 3/16" on the outside, bolted via 5/16" hex-heads and 5200 to the toerail, and another inside as a backing plate (roll it so you can get to the nuts inside!). It should be all right so long as the main bulkhead is adequately fastened (with 'glass or 5200) to the hull and deck at that location (you will need a 2" mousehole under the flange to slide the L-angle through). Remember that a stiff, mechanically-strong structure is worth more than sheer weight and size of the component parts.
The truth is that that toerail, if properly fastened and bedded everywhere else, isn't going to give up the ghost and pop off (nor even bend). Imagine how strong that 3-D shape is when held securely in a 3-D situation (crown, sheerline and curve of deck all at once). You'd break the wire or rip the fittings out of the (aged) spar before you broke the toerail.
(I don't know what the guy whose Catalina failed did, but I suspect his fasteners were all subpar and he had no backing plates.)
My only regret with this would be in losing pointing ability; and if you have a roller-furler and non-adjustable backstay you could become like all those other older-Hunter owners who complain their boats won't point so well 'any more', when it's all due to how they have 'modified' or maintained their own boats.
The best thing of course is to properly maintain, and fix when necessary, the structure you have; and you will benefit from good design, good seamanship, and even the good discipline it takes to keep up after it.
