1) Personally, I only use t1 or t2 relics in my LIs until I reach level cap. Then and only then worry about combining and such to get the best relics for my main LIs. Otherwise you're going to be buying lots of relic removal scrolls.
2) Assuming that you are mostly soloing/leveling, I agree with those who suggest maximizing DPS until you reach level cap or the point at which you start to group/instance/raid.
3) 2H sword gives more survivability (parry), one could argue so does 2H club (helps group out also), 2H axe or arguably 2H hammer are going to increase DPS just a tad. Draconfier nicely points out 2% racial bonus so 2H swords can also mean DPS. I think swords look cool but increasingly wonder if I should use something else for grouping (something that helps out the whole raid). I seldom need more threat from a halberd. And some use halberd just because we're the only class that can.
4) Personally, while leveling I would trade in my weapon every 3-5 levels to keep DPS up. If you have a 2nd Age or even 1st Age not so much. Decon at 31 then later decon at 60-61. (How does one decon at 61? By first burning a scroll of delving? Too expensive for my tastes.) I do recommend keeping track of which legacy scrolls you have on hand for later.
[U][COLOR=#40e0d0][B]Ngaemond 100[/B] [B]Cpt[/B][/COLOR][/U] | Ngeowyn 95 Wrd |[COLOR=#ee82ee] Ngamarie 95 Cpt[/COLOR](!?!) | Ngorbadoc 95 Hnt | Ngurin 95 Grd |[COLOR=#dda0dd] [URL="http://darkesthour-windfola.guildlaunch.com/"]Darkest Hour[/URL] - Windfola
[/COLOR][COLOR=#FF8C00][FONT=Verdana]Stop Crying about awesomeness... Captain was, is, and will be awesome. -MorningStarSE[/FONT][/COLOR]